/*    $OpenBSD: if_wpi.c,v 1.157 2022/04/21 21:03:03 stsp Exp $    */

/*-
 * Copyright (c) 2006-2008
 *    Damien Bergamini <damien.bergamini@free.fr>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * Driver for Intel PRO/Wireless 3945ABG 802.11 network adapters.
 */

#include "bpfilter.h"

#include <sys/param.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/task.h>
#include <sys/endian.h>

#include <machine/bus.h>
#include <machine/intr.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcidevs.h>

#if NBPFILTER > 0
#include <net/bpf.h>
#endif
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>

#include <netinet/in.h>
#include <netinet/if_ether.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_amrr.h>
#include <net80211/ieee80211_radiotap.h>

#include <dev/pci/if_wpireg.h>
#include <dev/pci/if_wpivar.h>

static const struct pci_matchid wpi_devices[] = {
    { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_PRO_WL_3945ABG_1 },
    { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_PRO_WL_3945ABG_2 }
};

int        wpi_match(struct device *, void *, void *);
void        wpi_attach(struct device *, struct device *, void *);
#if NBPFILTER > 0
void        wpi_radiotap_attach(struct wpi_softc *);
#endif
int        wpi_detach(struct device *, int);
int        wpi_activate(struct device *, int);
void        wpi_wakeup(struct wpi_softc *);
void        wpi_init_task(void *);
int        wpi_nic_lock(struct wpi_softc *);
int        wpi_read_prom_data(struct wpi_softc *, uint32_t, void *, int);
int        wpi_dma_contig_alloc(bus_dma_tag_t, struct wpi_dma_info *,
            void **, bus_size_t, bus_size_t);
void        wpi_dma_contig_free(struct wpi_dma_info *);
int        wpi_alloc_shared(struct wpi_softc *);
void        wpi_free_shared(struct wpi_softc *);
int        wpi_alloc_fwmem(struct wpi_softc *);
void        wpi_free_fwmem(struct wpi_softc *);
int        wpi_alloc_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
void        wpi_reset_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
void        wpi_free_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
int        wpi_alloc_tx_ring(struct wpi_softc *, struct wpi_tx_ring *,
            int);
void        wpi_reset_tx_ring(struct wpi_softc *, struct wpi_tx_ring *);
void        wpi_free_tx_ring(struct wpi_softc *, struct wpi_tx_ring *);
int        wpi_read_eeprom(struct wpi_softc *);
void        wpi_read_eeprom_channels(struct wpi_softc *, int);
void        wpi_read_eeprom_group(struct wpi_softc *, int);
struct        ieee80211_node *wpi_node_alloc(struct ieee80211com *);
void        wpi_newassoc(struct ieee80211com *, struct ieee80211_node *,
            int);
int        wpi_media_change(struct ifnet *);
int        wpi_newstate(struct ieee80211com *, enum ieee80211_state, int);
void        wpi_iter_func(void *, struct ieee80211_node *);
void        wpi_calib_timeout(void *);
int        wpi_ccmp_decap(struct wpi_softc *, mbuf_t,
            struct ieee80211_key *);
void        wpi_rx_done(struct wpi_softc *, struct wpi_rx_desc *,
            struct wpi_rx_data *, struct mbuf_list *);
void        wpi_tx_done(struct wpi_softc *, struct wpi_rx_desc *);
void        wpi_cmd_done(struct wpi_softc *, struct wpi_rx_desc *);
void        wpi_notif_intr(struct wpi_softc *);
void        wpi_fatal_intr(struct wpi_softc *);
int        wpi_intr(void *);
int        wpi_tx(struct wpi_softc *, mbuf_t,
            struct ieee80211_node *);
void        wpi_start(struct ifnet *);
void        wpi_watchdog(struct ifnet *);
int        wpi_ioctl(struct ifnet *, u_long, caddr_t);
int        wpi_cmd(struct wpi_softc *, int, const void *, int, int);
int        wpi_mrr_setup(struct wpi_softc *);
void        wpi_updateedca(struct ieee80211com *);
void        wpi_set_led(struct wpi_softc *, uint8_t, uint8_t, uint8_t);
int        wpi_set_timing(struct wpi_softc *, struct ieee80211_node *);
void        wpi_power_calibration(struct wpi_softc *);
int        wpi_set_txpower(struct wpi_softc *, int);
int        wpi_get_power_index(struct wpi_softc *,
            struct wpi_power_group *, struct ieee80211_channel *, int);
int        wpi_set_pslevel(struct wpi_softc *, int, int, int);
int        wpi_config(struct wpi_softc *);
int        wpi_scan(struct wpi_softc *, uint16_t);
int        wpi_auth(struct wpi_softc *);
int        wpi_run(struct wpi_softc *);
int        wpi_set_key(struct ieee80211com *, struct ieee80211_node *,
            struct ieee80211_key *);
void        wpi_delete_key(struct ieee80211com *, struct ieee80211_node *,
            struct ieee80211_key *);
int        wpi_post_alive(struct wpi_softc *);
int        wpi_load_bootcode(struct wpi_softc *, const uint8_t *, int);
int        wpi_load_firmware(struct wpi_softc *);
int        wpi_read_firmware(struct wpi_softc *);
int        wpi_clock_wait(struct wpi_softc *);
int        wpi_apm_init(struct wpi_softc *);
void        wpi_apm_stop_master(struct wpi_softc *);
void        wpi_apm_stop(struct wpi_softc *);
void        wpi_nic_config(struct wpi_softc *);
int        wpi_hw_init(struct wpi_softc *);
void        wpi_hw_stop(struct wpi_softc *);
int        wpi_init(struct ifnet *);
void        wpi_stop(struct ifnet *, int);

#ifdef WPI_DEBUG
#define DPRINTF(x)    do { if (wpi_debug > 0) printf x; } while (0)
#define DPRINTFN(n, x)    do { if (wpi_debug >= (n)) printf x; } while (0)
int wpi_debug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

struct cfdriver wpi_cd = {
    NULL, "wpi", DV_IFNET
};

const struct cfattach wpi_ca = {
    sizeof (struct wpi_softc), wpi_match, wpi_attach, wpi_detach,
    wpi_activate
};

int
wpi_match(struct device *parent, void *match, void *aux)
{
    return pci_matchbyid((struct pci_attach_args *)aux, wpi_devices,
        nitems(wpi_devices));
}

void
wpi_attach(struct device *parent, struct device *self, void *aux)
{
    struct wpi_softc *sc = (struct wpi_softc *)self;
    struct ieee80211com *ic = &sc->sc_ic;
    struct ifnet *ifp = &ic->ic_if;
    struct pci_attach_args *pa = (struct pci_attach_args *)aux;
    const char *intrstr;
    pci_intr_handle_t ih;
    pcireg_t memtype, reg;
    int i, error;

    sc->sc_pct = pa->pa_pc;
    sc->sc_pcitag = pa->pa_tag;
    sc->sc_dmat = pa->pa_dmat;

    /*
     * Get the offset of the PCI Express Capability Structure in PCI
     * Configuration Space (the vendor driver hard-codes it as E0h.)
     */
    error = pci_get_capability(sc->sc_pct, sc->sc_pcitag,
        PCI_CAP_PCIEXPRESS, &sc->sc_cap_off, NULL);
    if (error == 0) {
        printf(": PCIe capability structure not found!\n");
        return;
    }

    /* Clear device-specific "PCI retry timeout" register (41h). */
    reg = pci_conf_read(sc->sc_pct, sc->sc_pcitag, 0x40);
    reg &= ~0xff00;
    pci_conf_write(sc->sc_pct, sc->sc_pcitag, 0x40, reg);

    memtype = pci_mapreg_type(pa->pa_pc, pa->pa_tag, WPI_PCI_BAR0);
    error = pci_mapreg_map(pa, WPI_PCI_BAR0, memtype, 0, &sc->sc_st,
        &sc->sc_sh, NULL, &sc->sc_sz, 0);
    if (error != 0) {
        printf(": can't map mem space\n");
        return;
    }

    /* Install interrupt handler. */
    if (pci_intr_map_msi(pa, &ih) != 0 && pci_intr_map(pa, &ih) != 0) {
        printf(": can't map interrupt\n");
        return;
    }
    intrstr = pci_intr_string(sc->sc_pct, ih);
    sc->sc_ih = pci_intr_establish(sc->sc_pct, ih, IPL_NET, wpi_intr, sc,
        sc->sc_dev.dv_xname);
    if (sc->sc_ih == NULL) {
        printf(": can't establish interrupt");
        if (intrstr != NULL)
            printf(" at %s", intrstr);
        printf("\n");
        return;
    }
    printf(": %s", intrstr);
    
    snprintf(ifp->fwver, sizeof(ifp->fwver), "wpi-3945abg");

    /* Power ON adapter. */
    if ((error = wpi_apm_init(sc)) != 0) {
        printf(": could not power ON adapter\n");
        return;
    }

    /* Read MAC address, channels, etc from EEPROM. */
    if ((error = wpi_read_eeprom(sc)) != 0) {
        printf(": could not read EEPROM\n");
        return;
    }

    /* Allocate DMA memory for firmware transfers. */
    if ((error = wpi_alloc_fwmem(sc)) != 0) {
        printf(": could not allocate memory for firmware\n");
        return;
    }

    /* Allocate shared area. */
    if ((error = wpi_alloc_shared(sc)) != 0) {
        printf(": could not allocate shared area\n");
        goto fail1;
    }

    /* Allocate TX rings. */
    for (i = 0; i < WPI_NTXQUEUES; i++) {
        if ((error = wpi_alloc_tx_ring(sc, &sc->txq[i], i)) != 0) {
            printf(": could not allocate TX ring %d\n", i);
            goto fail2;
        }
    }

    /* Allocate RX ring. */
    if ((error = wpi_alloc_rx_ring(sc, &sc->rxq)) != 0) {
        printf(": could not allocate Rx ring\n");
        goto fail2;
    }

    /* Power OFF adapter. */
    wpi_apm_stop(sc);
    /* Clear pending interrupts. */
    WPI_WRITE(sc, WPI_INT, 0xffffffff);

    ic->ic_phytype = IEEE80211_T_OFDM;    /* not only, but not used */
    ic->ic_opmode = IEEE80211_M_STA;    /* default to BSS mode */
    ic->ic_state = IEEE80211_S_INIT;

    /* Set device capabilities. */
    ic->ic_caps =
        IEEE80211_C_WEP |        /* WEP */
        IEEE80211_C_RSN |        /* WPA/RSN */
        IEEE80211_C_SCANALL |    /* device scans all channels at once */
        IEEE80211_C_SCANALLBAND |    /* driver scans all bands at once */
        IEEE80211_C_MONITOR |    /* monitor mode supported */
        IEEE80211_C_SHSLOT |    /* short slot time supported */
        IEEE80211_C_SHPREAMBLE |    /* short preamble supported */
        IEEE80211_C_PMGT;        /* power saving supported */

    /* Set supported rates. */
    ic->ic_sup_rates[IEEE80211_MODE_11B] = ieee80211_std_rateset_11b;
    ic->ic_sup_rates[IEEE80211_MODE_11G] = ieee80211_std_rateset_11g;
    if (sc->sc_flags & WPI_FLAG_HAS_5GHZ) {
        ic->ic_sup_rates[IEEE80211_MODE_11A] =
            ieee80211_std_rateset_11a;
    }

    /* IBSS channel undefined for now. */
    ic->ic_ibss_chan = &ic->ic_channels[0];

    ifp->if_softc = sc;
    ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    ifp->if_ioctl = wpi_ioctl;
    ifp->if_start = wpi_start;
    ifp->if_watchdog = wpi_watchdog;
    memcpy(ifp->if_xname, sc->sc_dev.dv_xname, IFNAMSIZ);

    if_attach(ifp);
    ieee80211_ifattach(ifp);
    ic->ic_node_alloc = wpi_node_alloc;
    ic->ic_newassoc = wpi_newassoc;
    ic->ic_updateedca = wpi_updateedca;
    ic->ic_set_key = wpi_set_key;
    ic->ic_delete_key = wpi_delete_key;

    /* Override 802.11 state transition machine. */
    sc->sc_newstate = ic->ic_newstate;
    ic->ic_newstate = wpi_newstate;
    ieee80211_media_init(ifp, wpi_media_change, ieee80211_media_status);

    sc->amrr.amrr_min_success_threshold =  1;
    sc->amrr.amrr_max_success_threshold = 15;

#if NBPFILTER > 0
    wpi_radiotap_attach(sc);
#endif
    timeout_set(&sc->calib_to, wpi_calib_timeout, sc);
    rw_init(&sc->sc_rwlock, "wpilock");
    task_set(&sc->init_task, wpi_init_task, sc);
    return;

    /* Free allocated memory if something failed during attachment. */
fail2:    while (--i >= 0)
        wpi_free_tx_ring(sc, &sc->txq[i]);
    wpi_free_shared(sc);
fail1:    wpi_free_fwmem(sc);
}

#if NBPFILTER > 0
/*
 * Attach the interface to 802.11 radiotap.
 */
void
wpi_radiotap_attach(struct wpi_softc *sc)
{
    bpfattach(&sc->sc_drvbpf, &sc->sc_ic.ic_if, DLT_IEEE802_11_RADIO,
        sizeof (struct ieee80211_frame) + IEEE80211_RADIOTAP_HDRLEN);

    sc->sc_rxtap_len = sizeof sc->sc_rxtapu;
    sc->sc_rxtap.wr_ihdr.it_len = htole16(sc->sc_rxtap_len);
    sc->sc_rxtap.wr_ihdr.it_present = htole32(WPI_RX_RADIOTAP_PRESENT);

    sc->sc_txtap_len = sizeof sc->sc_txtapu;
    sc->sc_txtap.wt_ihdr.it_len = htole16(sc->sc_txtap_len);
    sc->sc_txtap.wt_ihdr.it_present = htole32(WPI_TX_RADIOTAP_PRESENT);
}
#endif

int
wpi_detach(struct device *self, int flags)
{
    struct wpi_softc *sc = (struct wpi_softc *)self;
    struct ifnet *ifp = &sc->sc_ic.ic_if;
    int qid;

    timeout_del(&sc->calib_to);
    task_del(systq, &sc->init_task);

    /* Uninstall interrupt handler. */
    if (sc->sc_ih != NULL)
        pci_intr_disestablish(sc->sc_pct, sc->sc_ih);

    /* Free DMA resources. */
    wpi_free_rx_ring(sc, &sc->rxq);
    for (qid = 0; qid < WPI_NTXQUEUES; qid++)
        wpi_free_tx_ring(sc, &sc->txq[qid]);
    wpi_free_shared(sc);
    wpi_free_fwmem(sc);

    bus_space_unmap(sc->sc_st, sc->sc_sh, sc->sc_sz);

    ieee80211_ifdetach(ifp);
    if_detach(ifp);

    return 0;
}

int
wpi_activate(struct device *self, int act)
{
    struct wpi_softc *sc = (struct wpi_softc *)self;
    struct ifnet *ifp = &sc->sc_ic.ic_if;

    switch (act) {
    case DVACT_SUSPEND:
        if (ifp->if_flags & IFF_RUNNING)
            wpi_stop(ifp, 0);
        break;
    case DVACT_WAKEUP:
        wpi_wakeup(sc);
        break;
    }

    return 0;
}

void
wpi_wakeup(struct wpi_softc *sc)
{
    pcireg_t reg;

    /* Clear device-specific "PCI retry timeout" register (41h). */
    reg = pci_conf_read(sc->sc_pct, sc->sc_pcitag, 0x40);
    reg &= ~0xff00;
    pci_conf_write(sc->sc_pct, sc->sc_pcitag, 0x40, reg);

    wpi_init_task(sc);
}

void
wpi_init_task(void *arg1)
{
    struct wpi_softc *sc = (struct wpi_softc *)arg1;
    struct ifnet *ifp = &sc->sc_ic.ic_if;
    int s;

    rw_enter_write(&sc->sc_rwlock);
    s = splnet();

    if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == IFF_UP)
        wpi_init(ifp);

    splx(s);
    rw_exit_write(&sc->sc_rwlock);
}

int
wpi_nic_lock(struct wpi_softc *sc)
{
    int ntries;

    /* Request exclusive access to NIC. */
    WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);

    /* Spin until we actually get the lock. */
    for (ntries = 0; ntries < 1000; ntries++) {
        if ((WPI_READ(sc, WPI_GP_CNTRL) &
             (WPI_GP_CNTRL_MAC_ACCESS_ENA | WPI_GP_CNTRL_SLEEP)) ==
            WPI_GP_CNTRL_MAC_ACCESS_ENA)
            return 0;
        DELAY(10);
    }
    return ETIMEDOUT;
}

static __inline void
wpi_nic_unlock(struct wpi_softc *sc)
{
    WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
}

static __inline uint32_t
wpi_prph_read(struct wpi_softc *sc, uint32_t addr)
{
    WPI_WRITE(sc, WPI_PRPH_RADDR, WPI_PRPH_DWORD | addr);
    WPI_BARRIER_READ_WRITE(sc);
    return WPI_READ(sc, WPI_PRPH_RDATA);
}

static __inline void
wpi_prph_write(struct wpi_softc *sc, uint32_t addr, uint32_t data)
{
    WPI_WRITE(sc, WPI_PRPH_WADDR, WPI_PRPH_DWORD | addr);
    WPI_BARRIER_WRITE(sc);
    WPI_WRITE(sc, WPI_PRPH_WDATA, data);
}

static __inline void
wpi_prph_setbits(struct wpi_softc *sc, uint32_t addr, uint32_t mask)
{
    wpi_prph_write(sc, addr, wpi_prph_read(sc, addr) | mask);
}

static __inline void
wpi_prph_clrbits(struct wpi_softc *sc, uint32_t addr, uint32_t mask)
{
    wpi_prph_write(sc, addr, wpi_prph_read(sc, addr) & ~mask);
}

static __inline void
wpi_prph_write_region_4(struct wpi_softc *sc, uint32_t addr,
    const uint32_t *data, int count)
{
    for (; count > 0; count--, data++, addr += 4)
        wpi_prph_write(sc, addr, *data);
}

#ifdef WPI_DEBUG

static __inline uint32_t
wpi_mem_read(struct wpi_softc *sc, uint32_t addr)
{
    WPI_WRITE(sc, WPI_MEM_RADDR, addr);
    WPI_BARRIER_READ_WRITE(sc);
    return WPI_READ(sc, WPI_MEM_RDATA);
}

static __inline void
wpi_mem_write(struct wpi_softc *sc, uint32_t addr, uint32_t data)
{
    WPI_WRITE(sc, WPI_MEM_WADDR, addr);
    WPI_BARRIER_WRITE(sc);
    WPI_WRITE(sc, WPI_MEM_WDATA, data);
}

static __inline void
wpi_mem_read_region_4(struct wpi_softc *sc, uint32_t addr, uint32_t *data,
    int count)
{
    for (; count > 0; count--, addr += 4)
        *data++ = wpi_mem_read(sc, addr);
}

#endif

int
wpi_read_prom_data(struct wpi_softc *sc, uint32_t addr, void *data, int count)
{
    uint8_t *out = (uint8_t *)data;
    uint32_t val;
    int error, ntries;

    if ((error = wpi_nic_lock(sc)) != 0)
        return error;

    for (; count > 0; count -= 2, addr++) {
        WPI_WRITE(sc, WPI_EEPROM, addr << 2);
        WPI_CLRBITS(sc, WPI_EEPROM, WPI_EEPROM_CMD);

        for (ntries = 0; ntries < 10; ntries++) {
            val = WPI_READ(sc, WPI_EEPROM);
            if (val & WPI_EEPROM_READ_VALID)
                break;
            DELAY(5);
        }
        if (ntries == 10) {
            printf("%s: could not read EEPROM\n",
                sc->sc_dev.dv_xname);
            return ETIMEDOUT;
        }
        *out++ = val >> 16;
        if (count > 1)
            *out++ = val >> 24;
    }

    wpi_nic_unlock(sc);
    return 0;
}

int
wpi_dma_contig_alloc(bus_dma_tag_t tag, struct wpi_dma_info *dma, void **kvap,
    bus_size_t size, bus_size_t alignment)
{
    int nsegs, error;

    dma->tag = tag;
    dma->size = size;

    error = bus_dmamap_create(tag, size, 1, size, 0, BUS_DMA_NOWAIT,
        &dma->map);
    if (error != 0)
        goto fail;

    error = bus_dmamem_alloc(tag, size, alignment, 0, &dma->seg, 1, &nsegs,
        BUS_DMA_NOWAIT | BUS_DMA_ZERO);
    if (error != 0)
        goto fail;

    error = bus_dmamem_map(tag, &dma->seg, 1, size, &dma->vaddr,
        BUS_DMA_NOWAIT | BUS_DMA_COHERENT);
    if (error != 0)
        goto fail;

    error = bus_dmamap_load_raw(tag, dma->map, &dma->seg, 1, size,
        BUS_DMA_NOWAIT);
    if (error != 0)
        goto fail;

    bus_dmamap_sync(tag, dma->map, 0, size, BUS_DMASYNC_PREWRITE);

    dma->paddr = dma->map->dm_segs[0].ds_addr;
    if (kvap != NULL)
        *kvap = dma->vaddr;

    return 0;

fail:    wpi_dma_contig_free(dma);
    return error;
}

void
wpi_dma_contig_free(struct wpi_dma_info *dma)
{
    if (dma->map != NULL) {
        if (dma->vaddr != NULL) {
            bus_dmamap_sync(dma->tag, dma->map, 0, dma->size,
                BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
            bus_dmamap_unload(dma->tag, dma->map);
            bus_dmamem_unmap(dma->tag, dma->vaddr, dma->size);
            bus_dmamem_free(dma->tag, &dma->seg, 1);
            dma->vaddr = NULL;
        }
        bus_dmamap_destroy(dma->tag, dma->map);
        dma->map = NULL;
    }
}

int
wpi_alloc_shared(struct wpi_softc *sc)
{
    /* Shared buffer must be aligned on a 4KB boundary. */
    return wpi_dma_contig_alloc(sc->sc_dmat, &sc->shared_dma,
        (void **)&sc->shared, sizeof (struct wpi_shared), 4096);
}

void
wpi_free_shared(struct wpi_softc *sc)
{
    wpi_dma_contig_free(&sc->shared_dma);
}

int
wpi_alloc_fwmem(struct wpi_softc *sc)
{
    /* Allocate enough contiguous space to store text and data. */
    return wpi_dma_contig_alloc(sc->sc_dmat, &sc->fw_dma, NULL,
        WPI_FW_TEXT_MAXSZ + WPI_FW_DATA_MAXSZ, 16);
}

void
wpi_free_fwmem(struct wpi_softc *sc)
{
    wpi_dma_contig_free(&sc->fw_dma);
}

int
wpi_alloc_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
    bus_size_t size;
    int i, error;

    ring->cur = 0;

    /* Allocate RX descriptors (16KB aligned.) */
    size = WPI_RX_RING_COUNT * sizeof (uint32_t);
    error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->desc_dma,
        (void **)&ring->desc, size, 16 * 1024);
    if (error != 0) {
        printf("%s: could not allocate RX ring DMA memory\n",
            sc->sc_dev.dv_xname);
        goto fail;
    }

    /*
     * Allocate and map RX buffers.
     */
    for (i = 0; i < WPI_RX_RING_COUNT; i++) {
        struct wpi_rx_data *data = &ring->data[i];

        error = bus_dmamap_create(sc->sc_dmat, WPI_RBUF_SIZE, 1,
            WPI_RBUF_SIZE, 0, BUS_DMA_NOWAIT, &data->map);
        if (error != 0) {
            printf("%s: could not create RX buf DMA map\n",
                sc->sc_dev.dv_xname);
            goto fail;
        }

        data->m = MCLGETL(NULL, M_DONTWAIT, WPI_RBUF_SIZE);
        if (data->m == NULL) {
            printf("%s: could not allocate RX mbuf\n",
                sc->sc_dev.dv_xname);
            error = ENOBUFS;
            goto fail;
        }

        error = bus_dmamap_load(sc->sc_dmat, data->map,
            mtod(data->m, void *), WPI_RBUF_SIZE, NULL,
            BUS_DMA_NOWAIT | BUS_DMA_READ);
        if (error != 0) {
            printf("%s: can't map mbuf (error %d)\n",
                sc->sc_dev.dv_xname, error);
            goto fail;
        }

        /* Set physical address of RX buffer. */
        ring->desc[i] = htole32(data->map->dm_segs[0].ds_addr);
    }

    bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0, size,
        BUS_DMASYNC_PREWRITE);

    return 0;

fail:    wpi_free_rx_ring(sc, ring);
    return error;
}

void
wpi_reset_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
    int ntries;

    if (wpi_nic_lock(sc) == 0) {
        WPI_WRITE(sc, WPI_FH_RX_CONFIG, 0);
        for (ntries = 0; ntries < 100; ntries++) {
            if (WPI_READ(sc, WPI_FH_RX_STATUS) &
                WPI_FH_RX_STATUS_IDLE)
                break;
            DELAY(10);
        }
        wpi_nic_unlock(sc);
    }
    ring->cur = 0;
}

void
wpi_free_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
    int i;

    wpi_dma_contig_free(&ring->desc_dma);

    for (i = 0; i < WPI_RX_RING_COUNT; i++) {
        struct wpi_rx_data *data = &ring->data[i];

        if (data->m != NULL) {
            bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                data->map->dm_mapsize, BUS_DMASYNC_POSTREAD);
            bus_dmamap_unload(sc->sc_dmat, data->map);
            m_freem(data->m);
        }
        if (data->map != NULL)
            bus_dmamap_destroy(sc->sc_dmat, data->map);
    }
}

int
wpi_alloc_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring, int qid)
{
    bus_addr_t paddr;
    bus_size_t size;
    int i, error;

    ring->qid = qid;
    ring->queued = 0;
    ring->cur = 0;

    /* Allocate TX descriptors (16KB aligned.) */
    size = WPI_TX_RING_COUNT * sizeof (struct wpi_tx_desc);
    error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->desc_dma,
        (void **)&ring->desc, size, 16 * 1024);
    if (error != 0) {
        printf("%s: could not allocate TX ring DMA memory\n",
            sc->sc_dev.dv_xname);
        goto fail;
    }

    /* Update shared area with ring physical address. */
    sc->shared->txbase[qid] = htole32(ring->desc_dma.paddr);
    bus_dmamap_sync(sc->sc_dmat, sc->shared_dma.map, 0,
        sizeof (struct wpi_shared), BUS_DMASYNC_PREWRITE);

    /*
     * We only use rings 0 through 4 (4 EDCA + cmd) so there is no need
     * to allocate commands space for other rings.
     * XXX Do we really need to allocate descriptors for other rings?
     */
    if (qid > 4)
        return 0;

    size = WPI_TX_RING_COUNT * sizeof (struct wpi_tx_cmd);
    error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->cmd_dma,
        (void **)&ring->cmd, size, 4);
    if (error != 0) {
        printf("%s: could not allocate TX cmd DMA memory\n",
            sc->sc_dev.dv_xname);
        goto fail;
    }

    paddr = ring->cmd_dma.paddr;
    for (i = 0; i < WPI_TX_RING_COUNT; i++) {
        struct wpi_tx_data *data = &ring->data[i];

        data->cmd_paddr = paddr;
        paddr += sizeof (struct wpi_tx_cmd);

        error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
            WPI_MAX_SCATTER - 1, MCLBYTES, 0, BUS_DMA_NOWAIT,
            &data->map);
        if (error != 0) {
            printf("%s: could not create TX buf DMA map\n",
                sc->sc_dev.dv_xname);
            goto fail;
        }
    }
    return 0;

fail:    wpi_free_tx_ring(sc, ring);
    return error;
}

void
wpi_reset_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{
    int i;

    for (i = 0; i < WPI_TX_RING_COUNT; i++) {
        struct wpi_tx_data *data = &ring->data[i];

        if (data->m != NULL) {
            bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
            bus_dmamap_unload(sc->sc_dmat, data->map);
            m_freem(data->m);
            data->m = NULL;
        }
    }
    /* Clear TX descriptors. */
    memset(ring->desc, 0, ring->desc_dma.size);
    sc->qfullmsk &= ~(1 << ring->qid);
    ring->queued = 0;
    ring->cur = 0;
}

void
wpi_free_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{
    int i;

    wpi_dma_contig_free(&ring->desc_dma);
    wpi_dma_contig_free(&ring->cmd_dma);

    for (i = 0; i < WPI_TX_RING_COUNT; i++) {
        struct wpi_tx_data *data = &ring->data[i];

        if (data->m != NULL) {
            bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
            bus_dmamap_unload(sc->sc_dmat, data->map);
            m_freem(data->m);
        }
        if (data->map != NULL)
            bus_dmamap_destroy(sc->sc_dmat, data->map);
    }
}

int
wpi_read_eeprom(struct wpi_softc *sc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    char domain[4];
    int i;

    if ((WPI_READ(sc, WPI_EEPROM_GP) & 0x6) == 0) {
        printf("%s: bad EEPROM signature\n", sc->sc_dev.dv_xname);
        return EIO;
    }
    /* Clear HW ownership of EEPROM. */
    WPI_CLRBITS(sc, WPI_EEPROM_GP, WPI_EEPROM_GP_IF_OWNER);

    wpi_read_prom_data(sc, WPI_EEPROM_CAPABILITIES, &sc->cap, 1);
    wpi_read_prom_data(sc, WPI_EEPROM_REVISION, &sc->rev, 2);
    wpi_read_prom_data(sc, WPI_EEPROM_TYPE, &sc->type, 1);

    DPRINTF(("cap=%x rev=%x type=%x\n", sc->cap, letoh16(sc->rev),
        sc->type));

    /* Read and print regulatory domain (4 ASCII characters.) */
    wpi_read_prom_data(sc, WPI_EEPROM_DOMAIN, domain, 4);
    printf(", %.4s", domain);

    /* Read and print MAC address. */
    wpi_read_prom_data(sc, WPI_EEPROM_MAC, ic->ic_myaddr, 6);
    printf(", address %s\n", ether_sprintf(ic->ic_myaddr));

    /* Read the list of authorized channels. */
    for (i = 0; i < WPI_CHAN_BANDS_COUNT; i++)
        wpi_read_eeprom_channels(sc, i);

    /* Read the list of TX power groups. */
    for (i = 0; i < WPI_POWER_GROUPS_COUNT; i++)
        wpi_read_eeprom_group(sc, i);

    return 0;
}

void
wpi_read_eeprom_channels(struct wpi_softc *sc, int n)
{
    struct ieee80211com *ic = &sc->sc_ic;
    const struct wpi_chan_band *band = &wpi_bands[n];
    struct wpi_eeprom_chan channels[WPI_MAX_CHAN_PER_BAND];
    int chan, i;

    wpi_read_prom_data(sc, band->addr, channels,
        band->nchan * sizeof (struct wpi_eeprom_chan));

    for (i = 0; i < band->nchan; i++) {
        if (!(channels[i].flags & WPI_EEPROM_CHAN_VALID))
            continue;

        chan = band->chan[i];

        if (n == 0) {    /* 2GHz band */
            ic->ic_channels[chan].ic_freq =
                ieee80211_ieee2mhz(chan, IEEE80211_CHAN_2GHZ);
            ic->ic_channels[chan].ic_flags =
                IEEE80211_CHAN_CCK | IEEE80211_CHAN_OFDM |
                IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;

        } else {    /* 5GHz band */
            /*
             * Some adapters support channels 7, 8, 11 and 12
             * both in the 2GHz and 4.9GHz bands.
             * Because of limitations in our net80211 layer,
             * we don't support them in the 4.9GHz band.
             */
            if (chan <= 14)
                continue;

            ic->ic_channels[chan].ic_freq =
                ieee80211_ieee2mhz(chan, IEEE80211_CHAN_5GHZ);
            ic->ic_channels[chan].ic_flags = IEEE80211_CHAN_A;
            /* We have at least one valid 5GHz channel. */
            sc->sc_flags |= WPI_FLAG_HAS_5GHZ;
        }

        /* Is active scan allowed on this channel? */
        if (!(channels[i].flags & WPI_EEPROM_CHAN_ACTIVE)) {
            ic->ic_channels[chan].ic_flags |=
                IEEE80211_CHAN_PASSIVE;
        }

        /* Save maximum allowed TX power for this channel. */
        sc->maxpwr[chan] = channels[i].maxpwr;

        DPRINTF(("adding chan %d flags=0x%x maxpwr=%d\n",
            chan, channels[i].flags, sc->maxpwr[chan]));
    }
}

void
wpi_read_eeprom_group(struct wpi_softc *sc, int n)
{
    struct wpi_power_group *group = &sc->groups[n];
    struct wpi_eeprom_group rgroup;
    int i;

    wpi_read_prom_data(sc, WPI_EEPROM_POWER_GRP + n * 32, &rgroup,
        sizeof rgroup);

    /* Save TX power group information. */
    group->chan   = rgroup.chan;
    group->maxpwr = rgroup.maxpwr;
    /* Retrieve temperature at which the samples were taken. */
    group->temp   = (int16_t)letoh16(rgroup.temp);

    DPRINTF(("power group %d: chan=%d maxpwr=%d temp=%d\n", n,
        group->chan, group->maxpwr, group->temp));

    for (i = 0; i < WPI_SAMPLES_COUNT; i++) {
        group->samples[i].index = rgroup.samples[i].index;
        group->samples[i].power = rgroup.samples[i].power;

        DPRINTF(("\tsample %d: index=%d power=%d\n", i,
            group->samples[i].index, group->samples[i].power));
    }
}

struct ieee80211_node *
wpi_node_alloc(struct ieee80211com *ic)
{
    return (struct ieee80211_node *)malloc(sizeof (struct wpi_node), M_DEVBUF, M_NOWAIT | M_ZERO);
}

void
wpi_newassoc(struct ieee80211com *ic, struct ieee80211_node *ni, int isnew)
{
    struct wpi_softc *sc = (typeof sc)ic->ic_if.if_softc;
    struct wpi_node *wn = (typeof wn)ni;
    uint8_t rate;
    int ridx, i;

    ieee80211_amrr_node_init(&sc->amrr, &wn->amn);
    /* Start at lowest available bit-rate, AMRR will raise. */
    ni->ni_txrate = 0;

    for (i = 0; i < ni->ni_rates.rs_nrates; i++) {
        rate = ni->ni_rates.rs_rates[i] & IEEE80211_RATE_VAL;
        /* Map 802.11 rate to HW rate index. */
        for (ridx = 0; ridx <= WPI_RIDX_MAX; ridx++)
            if (wpi_rates[ridx].rate == rate)
                break;
        wn->ridx[i] = ridx;
    }
}

int
wpi_media_change(struct ifnet *ifp)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    struct ieee80211com *ic = &sc->sc_ic;
    uint8_t rate, ridx;
    int error;

    error = ieee80211_media_change(ifp);
    if (error != ENETRESET)
        return error;

    if (ic->ic_fixed_rate != -1) {
        rate = ic->ic_sup_rates[ic->ic_curmode].
            rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL;
        /* Map 802.11 rate to HW rate index. */
        for (ridx = 0; ridx <= WPI_RIDX_MAX; ridx++)
            if (wpi_rates[ridx].rate == rate)
                break;
        sc->fixed_ridx = ridx;
    }

    if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
        (IFF_UP | IFF_RUNNING)) {
        wpi_stop(ifp, 0);
        error = wpi_init(ifp);
    }
    return error;
}

int
wpi_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
    struct ifnet *ifp = &ic->ic_if;
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    int error;

    timeout_del(&sc->calib_to);

    switch (nstate) {
    case IEEE80211_S_SCAN:
        /* Make the link LED blink while we're scanning. */
        wpi_set_led(sc, WPI_LED_LINK, 20, 2);

        if ((error = wpi_scan(sc, IEEE80211_CHAN_2GHZ)) != 0) {
            printf("%s: could not initiate scan\n",
                sc->sc_dev.dv_xname);
            return error;
        }
        if (ifp->if_flags & IFF_DEBUG)
            printf("%s: %s -> %s\n", ifp->if_xname,
                ieee80211_state_name[ic->ic_state],
                ieee80211_state_name[nstate]);
        ieee80211_set_link_state(ic, LINK_STATE_DOWN);
        ieee80211_node_cleanup(ic, ic->ic_bss);
        ic->ic_state = nstate;
        return 0;

    case IEEE80211_S_ASSOC:
        if (ic->ic_state != IEEE80211_S_RUN)
            break;
        /* FALLTHROUGH */
    case IEEE80211_S_AUTH:
        /* Reset state to handle reassociations correctly. */
        sc->rxon.associd = 0;
        sc->rxon.filter &= ~htole32(WPI_FILTER_BSS);

        if ((error = wpi_auth(sc)) != 0) {
            printf("%s: could not move to auth state\n",
                sc->sc_dev.dv_xname);
            return error;
        }
        break;

    case IEEE80211_S_RUN:
        if ((error = wpi_run(sc)) != 0) {
            printf("%s: could not move to run state\n",
                sc->sc_dev.dv_xname);
            return error;
        }
        break;

    case IEEE80211_S_INIT:
        break;
    }

    return sc->sc_newstate(ic, nstate, arg);
}

void
wpi_iter_func(void *arg, struct ieee80211_node *ni)
{
    struct wpi_softc *sc = (typeof sc)arg;
    struct wpi_node *wn = (struct wpi_node *)ni;

    ieee80211_amrr_choose(&sc->amrr, ni, &wn->amn);
}

void
wpi_calib_timeout(void *arg)
{
    struct wpi_softc *sc = (typeof sc)arg;
    struct ieee80211com *ic = &sc->sc_ic;
    int s;

    s = splnet();
    /* Automatic rate control triggered every 500ms. */
    if (ic->ic_fixed_rate == -1) {
        if (ic->ic_opmode == IEEE80211_M_STA)
            wpi_iter_func(sc, ic->ic_bss);
        else
            ieee80211_iterate_nodes(ic, wpi_iter_func, sc);
    }

    /* Force automatic TX power calibration every 60 secs. */
    if (++sc->calib_cnt >= 120) {
        wpi_power_calibration(sc);
        sc->calib_cnt = 0;
    }
    splx(s);

    /* Automatic rate control triggered every 500ms. */
    timeout_add_msec(&sc->calib_to, 500);
}

int
wpi_ccmp_decap(struct wpi_softc *sc, mbuf_t m, struct ieee80211_key *k)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ieee80211_frame *wh;
    uint64_t pn, *prsc;
    uint8_t *ivp;
    uint8_t tid;
    int hdrlen;

    wh = mtod(m, struct ieee80211_frame *);
    hdrlen = ieee80211_get_hdrlen(wh);
    ivp = (uint8_t *)wh + hdrlen;

    /* Check that ExtIV bit is set. */
    if (!(ivp[3] & IEEE80211_WEP_EXTIV)) {
        DPRINTF(("CCMP decap ExtIV not set\n"));
        return 1;
    }
    tid = ieee80211_has_qos(wh) ?
        ieee80211_get_qos(wh) & IEEE80211_QOS_TID : 0;
    prsc = &k->k_rsc[tid];

    /* Extract the 48-bit PN from the CCMP header. */
    pn = (uint64_t)ivp[0]       |
         (uint64_t)ivp[1] <<  8 |
         (uint64_t)ivp[4] << 16 |
         (uint64_t)ivp[5] << 24 |
         (uint64_t)ivp[6] << 32 |
         (uint64_t)ivp[7] << 40;
    if (pn <= *prsc) {
        DPRINTF(("CCMP replayed\n"));
        ic->ic_stats.is_ccmp_replays++;
        return 1;
    }
    /* Last seen packet number is updated in ieee80211_inputm(). */

    /* Strip MIC. IV will be stripped by ieee80211_inputm(). */
    m_adj(m, -IEEE80211_CCMP_MICLEN);
    return 0;
}

void
wpi_rx_done(struct wpi_softc *sc, struct wpi_rx_desc *desc,
    struct wpi_rx_data *data, struct mbuf_list *ml)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ifnet *ifp = &ic->ic_if;
    struct wpi_rx_ring *ring = &sc->rxq;
    struct wpi_rx_stat *stat;
    struct wpi_rx_head *head;
    struct wpi_rx_tail *tail;
    struct ieee80211_frame *wh;
    struct ieee80211_rxinfo rxi;
    struct ieee80211_node *ni;
    mbuf_t m, m1;
    uint32_t flags;
    int error;

    bus_dmamap_sync(sc->sc_dmat, data->map, 0, WPI_RBUF_SIZE,
        BUS_DMASYNC_POSTREAD);
    stat = (struct wpi_rx_stat *)(desc + 1);

    if (stat->len > WPI_STAT_MAXLEN) {
        printf("%s: invalid RX statistic header\n",
            sc->sc_dev.dv_xname);
        ifp->if_ierrors++;
        return;
    }
    head = (struct wpi_rx_head *)((caddr_t)(stat + 1) + stat->len);
    tail = (struct wpi_rx_tail *)((caddr_t)(head + 1) + letoh16(head->len));
    flags = letoh32(tail->flags);

    /* Discard frames with a bad FCS early. */
    if ((flags & WPI_RX_NOERROR) != WPI_RX_NOERROR) {
        DPRINTFN(2, ("rx tail flags error %x\n", flags));
        ifp->if_ierrors++;
        return;
    }
    /* Discard frames that are too short. */
    if (letoh16(head->len) < sizeof (*wh)) {
        DPRINTF(("frame too short: %d\n", letoh16(head->len)));
        ic->ic_stats.is_rx_tooshort++;
        ifp->if_ierrors++;
        return;
    }

    m1 = MCLGETL(NULL, M_DONTWAIT, WPI_RBUF_SIZE);
    if (m1 == NULL) {
        ic->ic_stats.is_rx_nombuf++;
        ifp->if_ierrors++;
        return;
    }
    bus_dmamap_unload(sc->sc_dmat, data->map);

    error = bus_dmamap_load(sc->sc_dmat, data->map, mtod(m1, void *),
        WPI_RBUF_SIZE, NULL, BUS_DMA_NOWAIT | BUS_DMA_READ);
    if (error != 0) {
        m_freem(m1);

        /* Try to reload the old mbuf. */
        error = bus_dmamap_load(sc->sc_dmat, data->map,
            mtod(data->m, void *), WPI_RBUF_SIZE, NULL,
            BUS_DMA_NOWAIT | BUS_DMA_READ);
        if (error != 0) {
            panic("%s: could not load old RX mbuf",
                sc->sc_dev.dv_xname);
        }
        /* Physical address may have changed. */
        ring->desc[ring->cur] = htole32(data->map->dm_segs[0].ds_addr);
        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map,
            ring->cur * sizeof (uint32_t), sizeof (uint32_t),
            BUS_DMASYNC_PREWRITE);
        ifp->if_ierrors++;
        return;
    }

    m = data->m;
    data->m = m1;
    /* Update RX descriptor. */
    ring->desc[ring->cur] = htole32(data->map->dm_segs[0].ds_addr);
    bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map,
        ring->cur * sizeof (uint32_t), sizeof (uint32_t),
        BUS_DMASYNC_PREWRITE);

    /* Finalize mbuf. */
    mbuf_setdata(m, (caddr_t)(head + 1), letoh16(head->len));
    mbuf_pkthdr_setlen(m, letoh16(head->len));
    mbuf_setlen(m, letoh16(head->len));

    /* Grab a reference to the source node. */
    wh = mtod(m, struct ieee80211_frame *);
    ni = ieee80211_find_rxnode(ic, wh);

    memset(&rxi, 0, sizeof(rxi));
    if ((wh->i_fc[1] & IEEE80211_FC1_PROTECTED) &&
        !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
        (ni->ni_flags & IEEE80211_NODE_RXPROT) &&
        ni->ni_pairwise_key.k_cipher == IEEE80211_CIPHER_CCMP) {
        if ((flags & WPI_RX_CIPHER_MASK) != WPI_RX_CIPHER_CCMP) {
            ic->ic_stats.is_ccmp_dec_errs++;
            ifp->if_ierrors++;
            m_freem(m);
            ieee80211_release_node(ic, ni);
            return;
        }
        /* Check whether decryption was successful or not. */
        if ((flags & WPI_RX_DECRYPT_MASK) != WPI_RX_DECRYPT_OK) {
            DPRINTF(("CCMP decryption failed 0x%x\n", flags));
            ic->ic_stats.is_ccmp_dec_errs++;
            ifp->if_ierrors++;
            m_freem(m);
            ieee80211_release_node(ic, ni);
            return;
        }
        if (wpi_ccmp_decap(sc, m, &ni->ni_pairwise_key) != 0) {
            ifp->if_ierrors++;
            m_freem(m);
            ieee80211_release_node(ic, ni);
            return;
        }
        rxi.rxi_flags |= IEEE80211_RXI_HWDEC;
    }

#if NBPFILTER > 0
    if (sc->sc_drvbpf != NULL) {
        struct wpi_rx_radiotap_header *tap = &sc->sc_rxtap;

        tap->wr_flags = 0;
        if (letoh16(head->flags) & 0x4)
            tap->wr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
        tap->wr_chan_freq =
            htole16(ic->ic_channels[head->chan].ic_freq);
        tap->wr_chan_flags =
            htole16(ic->ic_channels[head->chan].ic_flags);
        tap->wr_dbm_antsignal = (int8_t)(stat->rssi - WPI_RSSI_OFFSET);
        tap->wr_dbm_antnoise = (int8_t)letoh16(stat->noise);
        tap->wr_tsft = tail->tstamp;
        tap->wr_antenna = (letoh16(head->flags) >> 4) & 0xf;
        switch (head->rate) {
        /* CCK rates. */
        case  10: tap->wr_rate =   2; break;
        case  20: tap->wr_rate =   4; break;
        case  55: tap->wr_rate =  11; break;
        case 110: tap->wr_rate =  22; break;
        /* OFDM rates. */
        case 0xd: tap->wr_rate =  12; break;
        case 0xf: tap->wr_rate =  18; break;
        case 0x5: tap->wr_rate =  24; break;
        case 0x7: tap->wr_rate =  36; break;
        case 0x9: tap->wr_rate =  48; break;
        case 0xb: tap->wr_rate =  72; break;
        case 0x1: tap->wr_rate =  96; break;
        case 0x3: tap->wr_rate = 108; break;
        /* Unknown rate: should not happen. */
        default:  tap->wr_rate =   0;
        }

        bpf_mtap_hdr(sc->sc_drvbpf, tap, sc->sc_rxtap_len,
            m, BPF_DIRECTION_IN);
    }
#endif

    /* Send the frame to the 802.11 layer. */
    rxi.rxi_rssi = stat->rssi;
    ieee80211_inputm(ifp, m, ni, &rxi, ml);

    /* Node is no longer needed. */
    ieee80211_release_node(ic, ni);
}

void
wpi_tx_done(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ifnet *ifp = &ic->ic_if;
    struct wpi_tx_ring *ring = &sc->txq[desc->qid & 0x3];
    struct wpi_tx_data *data = &ring->data[desc->idx];
    struct wpi_tx_stat *stat = (struct wpi_tx_stat *)(desc + 1);
    struct wpi_node *wn = (struct wpi_node *)data->ni;

    /* Update rate control statistics. */
    wn->amn.amn_txcnt++;
    if (stat->retrycnt > 0)
        wn->amn.amn_retrycnt++;

    if ((letoh32(stat->status) & 0xff) != 1)
        ifp->if_oerrors++;

    /* Unmap and free mbuf. */
    bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
        BUS_DMASYNC_POSTWRITE);
    bus_dmamap_unload(sc->sc_dmat, data->map);
    m_freem(data->m);
    data->m = NULL;
    ieee80211_release_node(ic, data->ni);
    data->ni = NULL;

    sc->sc_tx_timer = 0;
    if (--ring->queued < WPI_TX_RING_LOMARK) {
        sc->qfullmsk &= ~(1 << ring->qid);
        if (sc->qfullmsk == 0 && ifq_is_oactive(&ifp->if_snd)) {
            ifq_clr_oactive(&ifp->if_snd);
            (*ifp->if_start)(ifp);
        }
    }
}

void
wpi_cmd_done(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
    struct wpi_tx_ring *ring = &sc->txq[4];
    struct wpi_tx_data *data;

    if ((desc->qid & 7) != 4)
        return;    /* Not a command ack. */

    data = &ring->data[desc->idx];

    /* If the command was mapped in an mbuf, free it. */
    if (data->m != NULL) {
        bus_dmamap_sync(sc->sc_dmat, data->map, 0,
            data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
        bus_dmamap_unload(sc->sc_dmat, data->map);
        m_freem(data->m);
        data->m = NULL;
    }
    wakeup(&ring->cmd[desc->idx]);
}

void
wpi_notif_intr(struct wpi_softc *sc)
{
    struct mbuf_list ml = MBUF_LIST_INITIALIZER();
    struct ieee80211com *ic = &sc->sc_ic;
    struct ifnet *ifp = &ic->ic_if;
    uint32_t hw;

    bus_dmamap_sync(sc->sc_dmat, sc->shared_dma.map, 0,
        sizeof (struct wpi_shared), BUS_DMASYNC_POSTREAD);

    hw = letoh32(sc->shared->next);
    while (sc->rxq.cur != hw) {
        struct wpi_rx_data *data = &sc->rxq.data[sc->rxq.cur];
        struct wpi_rx_desc *desc;

        bus_dmamap_sync(sc->sc_dmat, data->map, 0, sizeof (*desc),
            BUS_DMASYNC_POSTREAD);
        desc = mtod(data->m, struct wpi_rx_desc *);

        DPRINTFN(4, ("rx notification qid=%x idx=%d flags=%x type=%d "
            "len=%d\n", desc->qid, desc->idx, desc->flags, desc->type,
            letoh32(desc->len)));

        if (!(desc->qid & 0x80))    /* Reply to a command. */
            wpi_cmd_done(sc, desc);

        switch (desc->type) {
        case WPI_RX_DONE:
            /* An 802.11 frame has been received. */
            wpi_rx_done(sc, desc, data, &ml);
            break;

        case WPI_TX_DONE:
            /* An 802.11 frame has been transmitted. */
            wpi_tx_done(sc, desc);
            break;

        case WPI_UC_READY:
        {
            struct wpi_ucode_info *uc =
                (struct wpi_ucode_info *)(desc + 1);

            /* The microcontroller is ready. */
            bus_dmamap_sync(sc->sc_dmat, data->map, sizeof (*desc),
                sizeof (*uc), BUS_DMASYNC_POSTREAD);
            DPRINTF(("microcode alive notification version %x "
                "alive %x\n", letoh32(uc->version),
                letoh32(uc->valid)));

            if (letoh32(uc->valid) != 1) {
                printf("%s: microcontroller initialization "
                    "failed\n", sc->sc_dev.dv_xname);
            }
            if (uc->subtype != WPI_UCODE_INIT) {
                /* Save the address of the error log. */
                sc->errptr = letoh32(uc->errptr);
            }
            break;
        }
        case WPI_STATE_CHANGED:
        {
            uint32_t *status = (uint32_t *)(desc + 1);

            /* Enabled/disabled notification. */
            bus_dmamap_sync(sc->sc_dmat, data->map, sizeof (*desc),
                sizeof (*status), BUS_DMASYNC_POSTREAD);
            DPRINTF(("state changed to %x\n", letoh32(*status)));

            if (letoh32(*status) & 1) {
                /* The radio button has to be pushed. */
                printf("%s: Radio transmitter is off\n",
                    sc->sc_dev.dv_xname);
                /* Turn the interface down. */
                wpi_stop(ifp, 1);
                return;    /* No further processing. */
            }
            break;
        }
        case WPI_START_SCAN:
        {
            struct wpi_start_scan *scan =
                (struct wpi_start_scan *)(desc + 1);

            bus_dmamap_sync(sc->sc_dmat, data->map, sizeof (*desc),
                sizeof (*scan), BUS_DMASYNC_POSTREAD);
            DPRINTFN(2, ("scanning channel %d status %x\n",
                scan->chan, letoh32(scan->status)));

            /* Fix current channel. */
            ic->ic_bss->ni_chan = &ic->ic_channels[scan->chan];
            break;
        }
        case WPI_STOP_SCAN:
        {
            struct wpi_stop_scan *scan =
                (struct wpi_stop_scan *)(desc + 1);

            bus_dmamap_sync(sc->sc_dmat, data->map, sizeof (*desc),
                sizeof (*scan), BUS_DMASYNC_POSTREAD);
            DPRINTF(("scan finished nchan=%d status=%d chan=%d\n",
                scan->nchan, scan->status, scan->chan));

            if (scan->status == 1 && scan->chan <= 14 &&
                (sc->sc_flags & WPI_FLAG_HAS_5GHZ)) {
                /*
                 * We just finished scanning 2GHz channels,
                 * start scanning 5GHz ones.
                 */
                if (wpi_scan(sc, IEEE80211_CHAN_5GHZ) == 0)
                    break;
            }
            ieee80211_end_scan(ifp);
            break;
        }
        }

        sc->rxq.cur = (sc->rxq.cur + 1) % WPI_RX_RING_COUNT;
    }
    if_input(&ic->ic_if, &ml);

    /* Tell the firmware what we have processed. */
    hw = (hw == 0) ? WPI_RX_RING_COUNT - 1 : hw - 1;
    WPI_WRITE(sc, WPI_FH_RX_WPTR, hw & ~7);
}

#ifdef WPI_DEBUG
/*
 * Dump the error log of the firmware when a firmware panic occurs.  Although
 * we can't debug the firmware because it is neither open source nor free, it
 * can help us to identify certain classes of problems.
 */
void
wpi_fatal_intr(struct wpi_softc *sc)
{
#define N(a)    (sizeof (a) / sizeof ((a)[0]))
    struct wpi_fwdump dump;
    uint32_t i, offset, count;

    /* Check that the error log address is valid. */
    if (sc->errptr < WPI_FW_DATA_BASE ||
        sc->errptr + sizeof (dump) >
        WPI_FW_DATA_BASE + WPI_FW_DATA_MAXSZ) {
        printf("%s: bad firmware error log address 0x%08x\n",
            sc->sc_dev.dv_xname, sc->errptr);
        return;
    }

    if (wpi_nic_lock(sc) != 0) {
        printf("%s: could not read firmware error log\n",
            sc->sc_dev.dv_xname);
        return;
    }
    /* Read number of entries in the log. */
    count = wpi_mem_read(sc, sc->errptr);
    if (count == 0 || count * sizeof (dump) > WPI_FW_DATA_MAXSZ) {
        printf("%s: invalid count field (count=%u)\n",
            sc->sc_dev.dv_xname, count);
        wpi_nic_unlock(sc);
        return;
    }
    /* Skip "count" field. */
    offset = sc->errptr + sizeof (uint32_t);
    printf("firmware error log (count=%u):\n", count);
    for (i = 0; i < count; i++) {
        wpi_mem_read_region_4(sc, offset, (uint32_t *)&dump,
            sizeof (dump) / sizeof (uint32_t));

        printf("  error type = \"%s\" (0x%08X)\n",
            (dump.desc < N(wpi_fw_errmsg)) ?
            wpi_fw_errmsg[dump.desc] : "UNKNOWN",
            dump.desc);
        printf("  error data      = 0x%08X\n",
            dump.data);
        printf("  branch link     = 0x%08X%08X\n",
            dump.blink[0], dump.blink[1]);
        printf("  interrupt link  = 0x%08X%08X\n",
            dump.ilink[0], dump.ilink[1]);
        printf("  time            = %u\n", dump.time);

        offset += sizeof (dump);
    }
    wpi_nic_unlock(sc);
    /* Dump driver status (TX and RX rings) while we're here. */
    printf("driver status:\n");
    for (i = 0; i < 6; i++) {
        struct wpi_tx_ring *ring = &sc->txq[i];
        printf("  tx ring %2d: qid=%-2d cur=%-3d queued=%-3d\n",
            i, ring->qid, ring->cur, ring->queued);
    }
    printf("  rx ring: cur=%d\n", sc->rxq.cur);
    printf("  802.11 state %d\n", sc->sc_ic.ic_state);
#undef N
}
#endif

int
wpi_intr(void *arg)
{
    struct wpi_softc *sc = (typeof sc)arg;
    struct ifnet *ifp = &sc->sc_ic.ic_if;
    uint32_t r1, r2;

    /* Disable interrupts. */
    WPI_WRITE(sc, WPI_MASK, 0);

    r1 = WPI_READ(sc, WPI_INT);
    r2 = WPI_READ(sc, WPI_FH_INT);

    if (r1 == 0 && r2 == 0) {
        if (ifp->if_flags & IFF_UP)
            WPI_WRITE(sc, WPI_MASK, WPI_INT_MASK);
        return 0;    /* Interrupt not for us. */
    }
    if (r1 == 0xffffffff || (r1 & 0xfffffff0) == 0xa5a5a5a0)
        return 0;    /* Hardware gone! */

    /* Acknowledge interrupts. */
    WPI_WRITE(sc, WPI_INT, r1);
    WPI_WRITE(sc, WPI_FH_INT, r2);

    if (r1 & (WPI_INT_SW_ERR | WPI_INT_HW_ERR)) {
        printf("%s: fatal firmware error\n", sc->sc_dev.dv_xname);
        /* Dump firmware error log and stop. */
#ifdef WPI_DEBUG
        wpi_fatal_intr(sc);
#endif
        wpi_stop(ifp, 1);
        task_add(systq, &sc->init_task);
        return 1;
    }
    if ((r1 & (WPI_INT_FH_RX | WPI_INT_SW_RX)) ||
        (r2 & WPI_FH_INT_RX))
        wpi_notif_intr(sc);

    if (r1 & WPI_INT_ALIVE)
        wakeup(sc);    /* Firmware is alive. */

    /* Re-enable interrupts. */
    if (ifp->if_flags & IFF_UP)
        WPI_WRITE(sc, WPI_MASK, WPI_INT_MASK);

    return 1;
}

int
wpi_tx(struct wpi_softc *sc, mbuf_t m, struct ieee80211_node *ni)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct wpi_node *wn = (typeof wn)ni;
    struct wpi_tx_ring *ring;
    struct wpi_tx_desc *desc;
    struct wpi_tx_data *data;
    struct wpi_tx_cmd *cmd;
    struct wpi_cmd_data *tx;
    const struct wpi_rate *rinfo;
    struct ieee80211_frame *wh;
    struct ieee80211_key *k = NULL;
    enum ieee80211_edca_ac ac;
    uint32_t flags;
    uint16_t qos;
    u_int hdrlen;
    uint8_t *ivp, tid, ridx, type;
    int i, totlen, hasqos, error;

    wh = mtod(m, struct ieee80211_frame *);
    hdrlen = ieee80211_get_hdrlen(wh);
    type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;

    /* Select EDCA Access Category and TX ring for this frame. */
    if ((hasqos = ieee80211_has_qos(wh))) {
        qos = ieee80211_get_qos(wh);
        tid = qos & IEEE80211_QOS_TID;
        ac = ieee80211_up_to_ac(ic, tid);
    } else {
        tid = 0;
        ac = EDCA_AC_BE;
    }

    ring = &sc->txq[ac];
    desc = &ring->desc[ring->cur];
    data = &ring->data[ring->cur];

    /* Choose a TX rate index. */
    if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
        type != IEEE80211_FC0_TYPE_DATA) {
        ridx = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            WPI_RIDX_OFDM6 : WPI_RIDX_CCK1;
    } else if (ic->ic_fixed_rate != -1) {
        ridx = sc->fixed_ridx;
    } else
        ridx = wn->ridx[ni->ni_txrate];
    rinfo = &wpi_rates[ridx];

#if NBPFILTER > 0
    if (sc->sc_drvbpf != NULL) {
        struct wpi_tx_radiotap_header *tap = &sc->sc_txtap;

        tap->wt_flags = 0;
        tap->wt_chan_freq = htole16(ni->ni_chan->ic_freq);
        tap->wt_chan_flags = htole16(ni->ni_chan->ic_flags);
        tap->wt_rate = rinfo->rate;
        if ((ic->ic_flags & IEEE80211_F_WEPON) &&
            (wh->i_fc[1] & IEEE80211_FC1_PROTECTED))
            tap->wt_flags |= IEEE80211_RADIOTAP_F_WEP;

        bpf_mtap_hdr(sc->sc_drvbpf, tap, sc->sc_txtap_len,
            m, BPF_DIRECTION_OUT);
    }
#endif

    totlen = mbuf_pkthdr_len(m);

    /* Encrypt the frame if need be. */
    if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
        /* Retrieve key for TX. */
        k = ieee80211_get_txkey(ic, wh, ni);
        if (k->k_cipher != IEEE80211_CIPHER_CCMP) {
            /* Do software encryption. */
            if ((m = ieee80211_encrypt(ic, m, k)) == NULL)
                return ENOBUFS;
            /* 802.11 header may have moved. */
            wh = mtod(m, struct ieee80211_frame *);
            totlen = mbuf_pkthdr_len(m);

        } else    /* HW appends CCMP MIC. */
            totlen += IEEE80211_CCMP_HDRLEN;
    }

    /* Prepare TX firmware command. */
    cmd = &ring->cmd[ring->cur];
    cmd->code = WPI_CMD_TX_DATA;
    cmd->flags = 0;
    cmd->qid = ring->qid;
    cmd->idx = ring->cur;

    tx = (struct wpi_cmd_data *)cmd->data;
    /* NB: No need to clear tx, all fields are reinitialized here. */

    flags = 0;
    if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
        /* Unicast frame, check if an ACK is expected. */
        if (!hasqos || (qos & IEEE80211_QOS_ACK_POLICY_MASK) !=
            IEEE80211_QOS_ACK_POLICY_NOACK)
            flags |= WPI_TX_NEED_ACK;
    }

    /* Check if frame must be protected using RTS/CTS or CTS-to-self. */
    if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
        /* NB: Group frames are sent using CCK in 802.11b/g. */
        if (totlen + IEEE80211_CRC_LEN > ic->ic_rtsthreshold) {
            flags |= WPI_TX_NEED_RTS | WPI_TX_FULL_TXOP;
        } else if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
            ridx <= WPI_RIDX_OFDM54) {
            if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
                flags |= WPI_TX_NEED_CTS | WPI_TX_FULL_TXOP;
            else if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
                flags |= WPI_TX_NEED_RTS | WPI_TX_FULL_TXOP;
        }
    }

    if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
        type != IEEE80211_FC0_TYPE_DATA)
        tx->id = WPI_ID_BROADCAST;
    else
        tx->id = wn->id;

    if (type == IEEE80211_FC0_TYPE_MGT) {
        uint8_t subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;

#ifndef IEEE80211_STA_ONLY
        /* Tell HW to set timestamp in probe responses. */
        if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
            flags |= WPI_TX_INSERT_TSTAMP;
#endif
        if (subtype == IEEE80211_FC0_SUBTYPE_ASSOC_REQ ||
            subtype == IEEE80211_FC0_SUBTYPE_REASSOC_REQ)
            tx->timeout = htole16(3);
        else
            tx->timeout = htole16(2);
    } else
        tx->timeout = htole16(0);

    tx->len = htole16(totlen);
    tx->tid = tid;
    tx->rts_ntries = 7;
    tx->data_ntries = 15;
    tx->ofdm_mask = 0xff;
    tx->cck_mask = 0x0f;
    tx->lifetime = htole32(WPI_LIFETIME_INFINITE);
    tx->plcp = rinfo->plcp;

    /* Copy 802.11 header in TX command. */
    memcpy((uint8_t *)(tx + 1), wh, hdrlen);

    if (k != NULL && k->k_cipher == IEEE80211_CIPHER_CCMP) {
        /* Trim 802.11 header and prepend CCMP IV. */
        m_adj(m, hdrlen - IEEE80211_CCMP_HDRLEN);
        ivp = mtod(m, uint8_t *);
        k->k_tsc++;
        ivp[0] = k->k_tsc;
        ivp[1] = k->k_tsc >> 8;
        ivp[2] = 0;
        ivp[3] = k->k_id << 6 | IEEE80211_WEP_EXTIV;
        ivp[4] = k->k_tsc >> 16;
        ivp[5] = k->k_tsc >> 24;
        ivp[6] = k->k_tsc >> 32;
        ivp[7] = k->k_tsc >> 40;

        tx->security = WPI_CIPHER_CCMP;
        memcpy(tx->key, k->k_key, k->k_len);
    } else {
        /* Trim 802.11 header. */
        m_adj(m, hdrlen);
        tx->security = 0;
    }
    tx->flags = htole32(flags);

    error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m,
        BUS_DMA_NOWAIT | BUS_DMA_WRITE);
    if (error != 0 && error != EFBIG) {
        printf("%s: can't map mbuf (error %d)\n",
            sc->sc_dev.dv_xname, error);
        m_freem(m);
        return error;
    }
    if (error != 0) {
        /* Too many DMA segments, linearize mbuf. */
        if (m_defrag(m, M_DONTWAIT)) {
            m_freem(m);
            return ENOBUFS;
        }
        error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m,
            BUS_DMA_NOWAIT | BUS_DMA_WRITE);
        if (error != 0) {
            printf("%s: can't map mbuf (error %d)\n",
                sc->sc_dev.dv_xname, error);
            m_freem(m);
            return error;
        }
    }

    data->m = m;
    data->ni = ni;

    DPRINTFN(4, ("sending data: qid=%d idx=%d len=%d nsegs=%d\n",
        ring->qid, ring->cur, m->m_pkthdr.len, data->map->dm_nsegs));

    /* Fill TX descriptor. */
    desc->flags = htole32(WPI_PAD32(mbuf_pkthdr_len(m)) << 28 |
        (1 + data->map->dm_nsegs) << 24);
    /* First DMA segment is used by the TX command. */
    desc->segs[0].addr = htole32(ring->cmd_dma.paddr +
        ring->cur * sizeof (struct wpi_tx_cmd));
    desc->segs[0].len  = htole32(4 + sizeof (struct wpi_cmd_data) +
        ((hdrlen + 3) & ~3));
    /* Other DMA segments are for data payload. */
    for (i = 1; i <= data->map->dm_nsegs; i++) {
        desc->segs[i].addr =
            htole32(data->map->dm_segs[i - 1].ds_addr);
        desc->segs[i].len  =
            htole32(data->map->dm_segs[i - 1].ds_len);
    }

    bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
        BUS_DMASYNC_PREWRITE);
    bus_dmamap_sync(sc->sc_dmat, ring->cmd_dma.map,
        (caddr_t)cmd - ring->cmd_dma.vaddr, sizeof (*cmd),
        BUS_DMASYNC_PREWRITE);
    bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map,
        (caddr_t)desc - ring->desc_dma.vaddr, sizeof (*desc),
        BUS_DMASYNC_PREWRITE);

    /* Kick TX ring. */
    ring->cur = (ring->cur + 1) % WPI_TX_RING_COUNT;
    WPI_WRITE(sc, WPI_HBUS_TARG_WRPTR, ring->qid << 8 | ring->cur);

    /* Mark TX ring as full if we reach a certain threshold. */
    if (++ring->queued > WPI_TX_RING_HIMARK)
        sc->qfullmsk |= 1 << ring->qid;

    return 0;
}

void
wpi_start(struct ifnet *ifp)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    struct ieee80211com *ic = &sc->sc_ic;
    struct ieee80211_node *ni;
    mbuf_t m;

    if (!(ifp->if_flags & IFF_RUNNING) || ifq_is_oactive(&ifp->if_snd))
        return;

    for (;;) {
        if (sc->qfullmsk != 0) {
            ifq_set_oactive(&ifp->if_snd);
            break;
        }
        /* Send pending management frames first. */
        m = mq_dequeue(&ic->ic_mgtq);
        if (m != NULL) {
            ni = (struct ieee80211_node *)mbuf_pkthdr_rcvif(m);
            goto sendit;
        }
        if (!((struct device *)ifp->if_softc)->dev->useAppleRSNSupplicant(ifp->iface))
        if (ic->ic_state != IEEE80211_S_RUN)
            break;

        /* Encapsulate and send data frames. */
        m = ifq_dequeue(&ifp->if_snd);
        if (m == NULL)
            break;
#if NBPFILTER > 0
        if (ifp->if_bpf != NULL)
            bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT);
#endif
        if ((m = ieee80211_encap(ifp, m, &ni)) == NULL)
            continue;
sendit:
#if NBPFILTER > 0
        if (ic->ic_rawbpf != NULL)
            bpf_mtap(ic->ic_rawbpf, m, BPF_DIRECTION_OUT);
#endif
        if (wpi_tx(sc, m, ni) != 0) {
            ieee80211_release_node(ic, ni);
            ifp->if_oerrors++;
            continue;
        }

        sc->sc_tx_timer = 5;
        ifp->if_timer = 1;
    }
}

void
wpi_watchdog(struct ifnet *ifp)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;

    ifp->if_timer = 0;

    if (sc->sc_tx_timer > 0) {
        if (--sc->sc_tx_timer == 0) {
            printf("%s: device timeout\n", sc->sc_dev.dv_xname);
            wpi_stop(ifp, 1);
            ifp->if_oerrors++;
            return;
        }
        ifp->if_timer = 1;
    }

    ieee80211_watchdog(ifp);
}

int
wpi_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    struct ieee80211com *ic = &sc->sc_ic;
    int s, error = 0;

    error = rw_enter(&sc->sc_rwlock, RW_WRITE | RW_INTR);
    if (error)
        return error;
    s = splnet();

    switch (cmd) {
    case SIOCSIFADDR:
        ifp->if_flags |= IFF_UP;
        /* FALLTHROUGH */
    case SIOCSIFFLAGS:
        if (ifp->if_flags & IFF_UP) {
            if (!(ifp->if_flags & IFF_RUNNING))
                error = wpi_init(ifp);
        } else {
            if (ifp->if_flags & IFF_RUNNING)
                wpi_stop(ifp, 1);
        }
        break;

    case SIOCS80211POWER:
        error = ieee80211_ioctl(ifp, cmd, data);
        if (error != ENETRESET)
            break;
        if (ic->ic_state == IEEE80211_S_RUN) {
            if (ic->ic_flags & IEEE80211_F_PMGTON)
                error = wpi_set_pslevel(sc, 0, 3, 0);
            else    /* back to CAM */
                error = wpi_set_pslevel(sc, 0, 0, 0);
        } else {
            /* Defer until transition to IEEE80211_S_RUN. */
            error = 0;
        }
        break;

    default:
        error = ieee80211_ioctl(ifp, cmd, data);
    }

    if (error == ENETRESET) {
        error = 0;
        if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
            (IFF_UP | IFF_RUNNING)) {
            wpi_stop(ifp, 0);
            error = wpi_init(ifp);
        }
    }

    splx(s);
    rw_exit_write(&sc->sc_rwlock);
    return error;
}

/*
 * Send a command to the firmware.
 */
int
wpi_cmd(struct wpi_softc *sc, int code, const void *buf, int size, int async)
{
    struct wpi_tx_ring *ring = &sc->txq[4];
    struct wpi_tx_desc *desc;
    struct wpi_tx_data *data;
    struct wpi_tx_cmd *cmd;
    mbuf_t m;
    bus_addr_t paddr;
    int totlen, error;

    desc = &ring->desc[ring->cur];
    data = &ring->data[ring->cur];
    totlen = 4 + size;

    if (size > sizeof cmd->data) {
        /* Command is too large to fit in a descriptor. */
        if (totlen > MCLBYTES)
            return EINVAL;
        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == NULL)
            return ENOMEM;
        if (totlen > MHLEN) {
            MCLGET(m, M_DONTWAIT);
            if (!(mbuf_flags(m) & M_EXT)) {
                m_freem(m);
                return ENOMEM;
            }
        }
        cmd = mtod(m, struct wpi_tx_cmd *);
        error = bus_dmamap_load(sc->sc_dmat, data->map, cmd, totlen,
            NULL, BUS_DMA_NOWAIT | BUS_DMA_WRITE);
        if (error != 0) {
            m_freem(m);
            return error;
        }
        data->m = m;
        paddr = data->map->dm_segs[0].ds_addr;
    } else {
        cmd = &ring->cmd[ring->cur];
        paddr = data->cmd_paddr;
    }

    cmd->code = code;
    cmd->flags = 0;
    cmd->qid = ring->qid;
    cmd->idx = ring->cur;
    memcpy(cmd->data, buf, size);

    desc->flags = htole32(WPI_PAD32(size) << 28 | 1 << 24);
    desc->segs[0].addr = htole32(paddr);
    desc->segs[0].len  = htole32(totlen);

    if (size > sizeof cmd->data) {
        bus_dmamap_sync(sc->sc_dmat, data->map, 0, totlen,
            BUS_DMASYNC_PREWRITE);
    } else {
        bus_dmamap_sync(sc->sc_dmat, ring->cmd_dma.map,
            (caddr_t)cmd - ring->cmd_dma.vaddr, totlen,
            BUS_DMASYNC_PREWRITE);
    }
    bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map,
        (caddr_t)desc - ring->desc_dma.vaddr, sizeof (*desc),
        BUS_DMASYNC_PREWRITE);

    /* Kick command ring. */
    ring->cur = (ring->cur + 1) % WPI_TX_RING_COUNT;
    WPI_WRITE(sc, WPI_HBUS_TARG_WRPTR, ring->qid << 8 | ring->cur);

    return async ? 0 : tsleep_nsec(cmd, PCATCH, "wpicmd", SEC_TO_NSEC(1));
}

/*
 * Configure HW multi-rate retries.
 */
int
wpi_mrr_setup(struct wpi_softc *sc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct wpi_mrr_setup mrr;
    int i, error;

    /* CCK rates (not used with 802.11a). */
    for (i = WPI_RIDX_CCK1; i <= WPI_RIDX_CCK11; i++) {
        mrr.rates[i].flags = 0;
        mrr.rates[i].plcp = wpi_rates[i].plcp;
        /* Fallback to the immediate lower CCK rate (if any.) */
        mrr.rates[i].next =
            (i == WPI_RIDX_CCK1) ? WPI_RIDX_CCK1 : i - 1;
        /* Try one time at this rate before falling back to "next". */
        mrr.rates[i].ntries = 1;
    }
    /* OFDM rates (not used with 802.11b). */
    for (i = WPI_RIDX_OFDM6; i <= WPI_RIDX_OFDM54; i++) {
        mrr.rates[i].flags = 0;
        mrr.rates[i].plcp = wpi_rates[i].plcp;
        /* Fallback to the immediate lower rate (if any.) */
        /* We allow fallback from OFDM/6 to CCK/2 in 11b/g mode. */
        mrr.rates[i].next = (i == WPI_RIDX_OFDM6) ?
            ((ic->ic_curmode == IEEE80211_MODE_11A) ?
            WPI_RIDX_OFDM6 : WPI_RIDX_CCK2) :
            i - 1;
        /* Try one time at this rate before falling back to "next". */
        mrr.rates[i].ntries = 1;
    }
    /* Setup MRR for control frames. */
    mrr.which = htole32(WPI_MRR_CTL);
    error = wpi_cmd(sc, WPI_CMD_MRR_SETUP, &mrr, sizeof mrr, 0);
    if (error != 0) {
        printf("%s: could not setup MRR for control frames\n",
            sc->sc_dev.dv_xname);
        return error;
    }
    /* Setup MRR for data frames. */
    mrr.which = htole32(WPI_MRR_DATA);
    error = wpi_cmd(sc, WPI_CMD_MRR_SETUP, &mrr, sizeof mrr, 0);
    if (error != 0) {
        printf("%s: could not setup MRR for data frames\n",
            sc->sc_dev.dv_xname);
        return error;
    }
    return 0;
}

void
wpi_updateedca(struct ieee80211com *ic)
{
#define WPI_EXP2(x)    ((1 << (x)) - 1)    /* CWmin = 2^ECWmin - 1 */
    struct wpi_softc *sc = (typeof sc)ic->ic_softc;
    struct wpi_edca_params cmd;
    int aci;

    memset(&cmd, 0, sizeof cmd);
    cmd.flags = htole32(WPI_EDCA_UPDATE);
    for (aci = 0; aci < EDCA_NUM_AC; aci++) {
        const struct ieee80211_edca_ac_params *ac =
            &ic->ic_edca_ac[aci];
        cmd.ac[aci].aifsn = ac->ac_aifsn;
        cmd.ac[aci].cwmin = htole16(WPI_EXP2(ac->ac_ecwmin));
        cmd.ac[aci].cwmax = htole16(WPI_EXP2(ac->ac_ecwmax));
        cmd.ac[aci].txoplimit =
            htole16(IEEE80211_TXOP_TO_US(ac->ac_txoplimit));
    }
    (void)wpi_cmd(sc, WPI_CMD_EDCA_PARAMS, &cmd, sizeof cmd, 1);
#undef WPI_EXP2
}

void
wpi_set_led(struct wpi_softc *sc, uint8_t which, uint8_t off, uint8_t on)
{
    struct wpi_cmd_led led;

    led.which = which;
    led.unit = htole32(100000);    /* on/off in unit of 100ms */
    led.off = off;
    led.on = on;
    (void)wpi_cmd(sc, WPI_CMD_SET_LED, &led, sizeof led, 1);
}

int
wpi_set_timing(struct wpi_softc *sc, struct ieee80211_node *ni)
{
    struct wpi_cmd_timing cmd;
    uint64_t val, mod;

    memset(&cmd, 0, sizeof cmd);
    memcpy(&cmd.tstamp, ni->ni_tstamp, sizeof (uint64_t));
    cmd.bintval = htole16(ni->ni_intval);
    cmd.lintval = htole16(10);

    /* Compute remaining time until next beacon. */
    val = (uint64_t)ni->ni_intval * 1024;    /* msecs -> usecs */
    mod = letoh64(cmd.tstamp) % val;
    cmd.binitval = htole32((uint32_t)(val - mod));

    DPRINTF(("timing bintval=%u, tstamp=%llu, init=%u\n",
        ni->ni_intval, letoh64(cmd.tstamp), (uint32_t)(val - mod)));

    return wpi_cmd(sc, WPI_CMD_TIMING, &cmd, sizeof cmd, 1);
}

/*
 * This function is called periodically (every minute) to adjust TX power
 * based on temperature variation.
 */
void
wpi_power_calibration(struct wpi_softc *sc)
{
    int temp;

    temp = (int)WPI_READ(sc, WPI_UCODE_GP2);
    /* Sanity-check temperature. */
    if (temp < -260 || temp > 25) {
        /* This can't be correct, ignore. */
        DPRINTF(("out-of-range temperature reported: %d\n", temp));
        return;
    }
    DPRINTF(("temperature %d->%d\n", sc->temp, temp));
    /* Adjust TX power if need be (delta > 6). */
    if (abs(temp - sc->temp) > 6) {
        /* Record temperature of last calibration. */
        sc->temp = temp;
        (void)wpi_set_txpower(sc, 1);
    }
}

/*
 * Set TX power for current channel (each rate has its own power settings).
 */
int
wpi_set_txpower(struct wpi_softc *sc, int async)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ieee80211_channel *ch;
    struct wpi_power_group *group;
    struct wpi_cmd_txpower cmd;
    u_int chan;
    int idx, i;

    /* Retrieve current channel from last RXON. */
    chan = sc->rxon.chan;
    DPRINTF(("setting TX power for channel %d\n", chan));
    ch = &ic->ic_channels[chan];

    /* Find the TX power group to which this channel belongs. */
    if (IEEE80211_IS_CHAN_5GHZ(ch)) {
        for (group = &sc->groups[1]; group < &sc->groups[4]; group++)
            if (chan <= group->chan)
                break;
    } else
        group = &sc->groups[0];

    memset(&cmd, 0, sizeof cmd);
    cmd.band = IEEE80211_IS_CHAN_5GHZ(ch) ? 0 : 1;
    cmd.chan = htole16(chan);

    /* Set TX power for all OFDM and CCK rates. */
    for (i = 0; i <= WPI_RIDX_MAX ; i++) {
        /* Retrieve TX power for this channel/rate. */
        idx = wpi_get_power_index(sc, group, ch, i);

        cmd.rates[i].plcp = wpi_rates[i].plcp;

        if (IEEE80211_IS_CHAN_5GHZ(ch)) {
            cmd.rates[i].rf_gain = wpi_rf_gain_5ghz[idx];
            cmd.rates[i].dsp_gain = wpi_dsp_gain_5ghz[idx];
        } else {
            cmd.rates[i].rf_gain = wpi_rf_gain_2ghz[idx];
            cmd.rates[i].dsp_gain = wpi_dsp_gain_2ghz[idx];
        }
        DPRINTF(("chan %d/rate %d: power index %d\n", chan,
            wpi_rates[i].rate, idx));
    }
    return wpi_cmd(sc, WPI_CMD_TXPOWER, &cmd, sizeof cmd, async);
}

/*
 * Determine TX power index for a given channel/rate combination.
 * This takes into account the regulatory information from EEPROM and the
 * current temperature.
 */
int
wpi_get_power_index(struct wpi_softc *sc, struct wpi_power_group *group,
    struct ieee80211_channel *c, int ridx)
{
/* Fixed-point arithmetic division using a n-bit fractional part. */
#define fdivround(a, b, n)    \
    ((((1 << n) * (a)) / (b) + (1 << n) / 2) / (1 << n))

/* Linear interpolation. */
#define interpolate(x, x1, y1, x2, y2, n)    \
    ((y1) + fdivround(((x) - (x1)) * ((y2) - (y1)), (x2) - (x1), n))

    struct ieee80211com *ic = &sc->sc_ic;
    struct wpi_power_sample *sample;
    int pwr, idx;
    u_int chan;

    /* Get channel number. */
    chan = ieee80211_chan2ieee(ic, c);

    /* Default TX power is group maximum TX power minus 3dB. */
    pwr = group->maxpwr / 2;

    /* Decrease TX power for highest OFDM rates to reduce distortion. */
    switch (ridx) {
    case WPI_RIDX_OFDM36:
        pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 0 :  5;
        break;
    case WPI_RIDX_OFDM48:
        pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 7 : 10;
        break;
    case WPI_RIDX_OFDM54:
        pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 9 : 12;
        break;
    }

    /* Never exceed the channel maximum allowed TX power. */
    pwr = MIN(pwr, sc->maxpwr[chan]);

    /* Retrieve TX power index into gain tables from samples. */
    for (sample = group->samples; sample < &group->samples[3]; sample++)
        if (pwr > sample[1].power)
            break;
    /* Fixed-point linear interpolation using a 19-bit fractional part. */
    idx = interpolate(pwr, sample[0].power, sample[0].index,
        sample[1].power, sample[1].index, 19);

    /*-
     * Adjust power index based on current temperature:
     * - if cooler than factory-calibrated: decrease output power
     * - if warmer than factory-calibrated: increase output power
     */
    idx -= (sc->temp - group->temp) * 11 / 100;

    /* Decrease TX power for CCK rates (-5dB). */
    if (ridx >= WPI_RIDX_CCK1)
        idx += 10;

    /* Make sure idx stays in a valid range. */
    if (idx < 0)
        idx = 0;
    else if (idx > WPI_MAX_PWR_INDEX)
        idx = WPI_MAX_PWR_INDEX;
    return idx;

#undef interpolate
#undef fdivround
}

/*
 * Set STA mode power saving level (between 0 and 5).
 * Level 0 is CAM (Continuously Aware Mode), 5 is for maximum power saving.
 */
int
wpi_set_pslevel(struct wpi_softc *sc, int dtim, int level, int async)
{
    struct wpi_pmgt_cmd cmd;
    const struct wpi_pmgt *pmgt;
    uint32_t max, skip_dtim;
    pcireg_t reg;
    int i;

    /* Select which PS parameters to use. */
    if (dtim <= 10)
        pmgt = &wpi_pmgt[0][level];
    else
        pmgt = &wpi_pmgt[1][level];

    memset(&cmd, 0, sizeof cmd);
    if (level != 0)    /* not CAM */
        cmd.flags |= htole16(WPI_PS_ALLOW_SLEEP);
    /* Retrieve PCIe Active State Power Management (ASPM). */
    reg = pci_conf_read(sc->sc_pct, sc->sc_pcitag,
        sc->sc_cap_off + PCI_PCIE_LCSR);
    if (!(reg & PCI_PCIE_LCSR_ASPM_L0S))    /* L0s Entry disabled. */
        cmd.flags |= htole16(WPI_PS_PCI_PMGT);
    cmd.rxtimeout = htole32(pmgt->rxtimeout * 1024);
    cmd.txtimeout = htole32(pmgt->txtimeout * 1024);

    if (dtim == 0) {
        dtim = 1;
        skip_dtim = 0;
    } else
        skip_dtim = pmgt->skip_dtim;
    if (skip_dtim != 0) {
        cmd.flags |= htole16(WPI_PS_SLEEP_OVER_DTIM);
        max = pmgt->intval[4];
        if (max == (uint32_t)-1)
            max = dtim * (skip_dtim + 1);
        else if (max > dtim)
            max = (max / dtim) * dtim;
    } else
        max = dtim;
    for (i = 0; i < 5; i++)
        cmd.intval[i] = htole32(MIN(max, pmgt->intval[i]));

    DPRINTF(("setting power saving level to %d\n", level));
    return wpi_cmd(sc, WPI_CMD_SET_POWER_MODE, &cmd, sizeof cmd, async);
}

int
wpi_config(struct wpi_softc *sc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ifnet *ifp = &ic->ic_if;
    struct wpi_bluetooth bluetooth;
    struct wpi_node_info node;
    int error;

    /* Set power saving level to CAM during initialization. */
    if ((error = wpi_set_pslevel(sc, 0, 0, 0)) != 0) {
        printf("%s: could not set power saving level\n",
            sc->sc_dev.dv_xname);
        return error;
    }

    /* Configure bluetooth coexistence. */
    memset(&bluetooth, 0, sizeof bluetooth);
    bluetooth.flags = WPI_BT_COEX_MODE_4WIRE;
    bluetooth.lead_time = WPI_BT_LEAD_TIME_DEF;
    bluetooth.max_kill = WPI_BT_MAX_KILL_DEF;
    error = wpi_cmd(sc, WPI_CMD_BT_COEX, &bluetooth, sizeof bluetooth, 0);
    if (error != 0) {
        printf("%s: could not configure bluetooth coexistence\n",
            sc->sc_dev.dv_xname);
        return error;
    }

    /* Configure adapter. */
    memset(&sc->rxon, 0, sizeof (struct wpi_rxon));
    IEEE80211_ADDR_COPY(ic->ic_myaddr, LLADDR(ifp->if_sadl));
    IEEE80211_ADDR_COPY(sc->rxon.myaddr, ic->ic_myaddr);
    /* Set default channel. */
    sc->rxon.chan = ieee80211_chan2ieee(ic, ic->ic_ibss_chan);
    sc->rxon.flags = htole32(WPI_RXON_TSF);
    if (IEEE80211_IS_CHAN_2GHZ(ic->ic_ibss_chan))
        sc->rxon.flags |= htole32(WPI_RXON_AUTO | WPI_RXON_24GHZ);
    switch (ic->ic_opmode) {
    case IEEE80211_M_STA:
        sc->rxon.mode = WPI_MODE_STA;
        sc->rxon.filter = htole32(WPI_FILTER_MULTICAST);
        break;
    case IEEE80211_M_MONITOR:
        sc->rxon.mode = WPI_MODE_MONITOR;
        sc->rxon.filter = htole32(WPI_FILTER_MULTICAST |
            WPI_FILTER_CTL | WPI_FILTER_PROMISC);
        break;
    default:
        /* Should not get there. */
        break;
    }
    sc->rxon.cck_mask  = 0x0f;    /* not yet negotiated */
    sc->rxon.ofdm_mask = 0xff;    /* not yet negotiated */
    DPRINTF(("setting configuration\n"));
    error = wpi_cmd(sc, WPI_CMD_RXON, &sc->rxon, sizeof (struct wpi_rxon),
        0);
    if (error != 0) {
        printf("%s: RXON command failed\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Configuration has changed, set TX power accordingly. */
    if ((error = wpi_set_txpower(sc, 0)) != 0) {
        printf("%s: could not set TX power\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Add broadcast node. */
    memset(&node, 0, sizeof node);
    IEEE80211_ADDR_COPY(node.macaddr, etherbroadcastaddr);
    node.id = WPI_ID_BROADCAST;
    node.plcp = wpi_rates[WPI_RIDX_CCK1].plcp;
    node.action = htole32(WPI_ACTION_SET_RATE);
    node.antenna = WPI_ANTENNA_BOTH;
    error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 0);
    if (error != 0) {
        printf("%s: could not add broadcast node\n",
            sc->sc_dev.dv_xname);
        return error;
    }

    if ((error = wpi_mrr_setup(sc)) != 0) {
        printf("%s: could not setup MRR\n", sc->sc_dev.dv_xname);
        return error;
    }
    return 0;
}

int
wpi_scan(struct wpi_softc *sc, uint16_t flags)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct wpi_scan_hdr *hdr;
    struct wpi_cmd_data *tx;
    struct wpi_scan_essid *essid;
    struct wpi_scan_chan *chan;
    struct ieee80211_frame *wh;
    struct ieee80211_rateset *rs;
    struct ieee80211_channel *c;
    uint8_t *buf, *frm;
    int buflen, error;

    buf = (typeof buf)malloc(WPI_SCAN_MAXSZ, M_DEVBUF, M_NOWAIT | M_ZERO);
    if (buf == NULL) {
        printf("%s: could not allocate buffer for scan command\n",
            sc->sc_dev.dv_xname);
        return ENOMEM;
    }
    hdr = (struct wpi_scan_hdr *)buf;
    /*
     * Move to the next channel if no frames are received within 10ms
     * after sending the probe request.
     */
    hdr->quiet_time = htole16(10);        /* timeout in milliseconds */
    hdr->quiet_threshold = htole16(1);    /* min # of packets */

    tx = (struct wpi_cmd_data *)(hdr + 1);
    tx->flags = htole32(WPI_TX_AUTO_SEQ);
    tx->id = WPI_ID_BROADCAST;
    tx->lifetime = htole32(WPI_LIFETIME_INFINITE);

    if (flags & IEEE80211_CHAN_5GHZ) {
        hdr->crc_threshold = htole16(1);
        /* Send probe requests at 6Mbps. */
        tx->plcp = wpi_rates[WPI_RIDX_OFDM6].plcp;
        rs = &ic->ic_sup_rates[IEEE80211_MODE_11A];
    } else {
        hdr->flags = htole32(WPI_RXON_24GHZ | WPI_RXON_AUTO);
        /* Send probe requests at 1Mbps. */
        tx->plcp = wpi_rates[WPI_RIDX_CCK1].plcp;
        rs = &ic->ic_sup_rates[IEEE80211_MODE_11G];
    }

    essid = (struct wpi_scan_essid *)(tx + 1);
    if (ic->ic_des_esslen != 0) {
        essid[0].id  = IEEE80211_ELEMID_SSID;
        essid[0].len = ic->ic_des_esslen;
        memcpy(essid[0].data, ic->ic_des_essid, ic->ic_des_esslen);
    }
    /*
     * Build a probe request frame.  Most of the following code is a
     * copy & paste of what is done in net80211.
     */
    wh = (struct ieee80211_frame *)(essid + 4);
    wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
        IEEE80211_FC0_SUBTYPE_PROBE_REQ;
    wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
    IEEE80211_ADDR_COPY(wh->i_addr1, etherbroadcastaddr);
    IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
    IEEE80211_ADDR_COPY(wh->i_addr3, etherbroadcastaddr);
    *(uint16_t *)&wh->i_dur[0] = 0;    /* filled by HW */
    *(uint16_t *)&wh->i_seq[0] = 0;    /* filled by HW */

    frm = (uint8_t *)(wh + 1);
    frm = ieee80211_add_ssid(frm, NULL, 0);
    frm = ieee80211_add_rates(frm, rs);
    if (rs->rs_nrates > IEEE80211_RATE_SIZE)
        frm = ieee80211_add_xrates(frm, rs);

    /* Set length of probe request. */
    tx->len = htole16(frm - (uint8_t *)wh);

    chan = (struct wpi_scan_chan *)frm;
    for (c  = &ic->ic_channels[1];
         c <= &ic->ic_channels[IEEE80211_CHAN_MAX]; c++) {
        if ((c->ic_flags & flags) != flags)
            continue;

        chan->chan = ieee80211_chan2ieee(ic, c);
        DPRINTFN(2, ("adding channel %d\n", chan->chan));
        chan->flags = 0;
        if (!(c->ic_flags & IEEE80211_CHAN_PASSIVE))
            chan->flags |= WPI_CHAN_ACTIVE;
        if (ic->ic_des_esslen != 0)
            chan->flags |= WPI_CHAN_NPBREQS(1);
        chan->dsp_gain = 0x6e;
        if (IEEE80211_IS_CHAN_5GHZ(c)) {
            chan->rf_gain = 0x3b;
            chan->active  = htole16(24);
            chan->passive = htole16(110);
        } else {
            chan->rf_gain = 0x28;
            chan->active  = htole16(36);
            chan->passive = htole16(120);
        }
        hdr->nchan++;
        chan++;
    }

    buflen = (uint8_t *)chan - buf;
    hdr->len = htole16(buflen);

    DPRINTF(("sending scan command nchan=%d\n", hdr->nchan));
    error = wpi_cmd(sc, WPI_CMD_SCAN, buf, buflen, 1);
    free(buf, M_DEVBUF, WPI_SCAN_MAXSZ);
    return error;
}

int
wpi_auth(struct wpi_softc *sc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ieee80211_node *ni = ic->ic_bss;
    struct wpi_node_info node;
    int error;

    /* Update adapter configuration. */
    IEEE80211_ADDR_COPY(sc->rxon.bssid, ni->ni_bssid);
    sc->rxon.chan = ieee80211_chan2ieee(ic, ni->ni_chan);
    sc->rxon.flags = htole32(WPI_RXON_TSF);
    if (IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
        sc->rxon.flags |= htole32(WPI_RXON_AUTO | WPI_RXON_24GHZ);
    if (ic->ic_flags & IEEE80211_F_SHSLOT)
        sc->rxon.flags |= htole32(WPI_RXON_SHSLOT);
    if (ic->ic_flags & IEEE80211_F_SHPREAMBLE)
        sc->rxon.flags |= htole32(WPI_RXON_SHPREAMBLE);
    switch (ic->ic_curmode) {
    case IEEE80211_MODE_11A:
        sc->rxon.cck_mask  = 0;
        sc->rxon.ofdm_mask = 0x15;
        break;
    case IEEE80211_MODE_11B:
        sc->rxon.cck_mask  = 0x03;
        sc->rxon.ofdm_mask = 0;
        break;
    default:    /* Assume 802.11b/g. */
        sc->rxon.cck_mask  = 0x0f;
        sc->rxon.ofdm_mask = 0x15;
    }
    DPRINTF(("rxon chan %d flags %x cck %x ofdm %x\n", sc->rxon.chan,
        sc->rxon.flags, sc->rxon.cck_mask, sc->rxon.ofdm_mask));
    error = wpi_cmd(sc, WPI_CMD_RXON, &sc->rxon, sizeof (struct wpi_rxon),
        1);
    if (error != 0) {
        printf("%s: RXON command failed\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Configuration has changed, set TX power accordingly. */
    if ((error = wpi_set_txpower(sc, 1)) != 0) {
        printf("%s: could not set TX power\n", sc->sc_dev.dv_xname);
        return error;
    }
    /*
     * Reconfiguring RXON clears the firmware nodes table so we must
     * add the broadcast node again.
     */
    memset(&node, 0, sizeof node);
    IEEE80211_ADDR_COPY(node.macaddr, etherbroadcastaddr);
    node.id = WPI_ID_BROADCAST;
    node.plcp = (ic->ic_curmode == IEEE80211_MODE_11A) ?
        wpi_rates[WPI_RIDX_OFDM6].plcp : wpi_rates[WPI_RIDX_CCK1].plcp;
    node.action = htole32(WPI_ACTION_SET_RATE);
    node.antenna = WPI_ANTENNA_BOTH;
    error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
    if (error != 0) {
        printf("%s: could not add broadcast node\n",
            sc->sc_dev.dv_xname);
        return error;
    }
    return 0;
}

int
wpi_run(struct wpi_softc *sc)
{
    struct ieee80211com *ic = &sc->sc_ic;
    struct ieee80211_node *ni = ic->ic_bss;
    struct wpi_node_info node;
    int error;

    if (ic->ic_opmode == IEEE80211_M_MONITOR) {
        /* Link LED blinks while monitoring. */
        wpi_set_led(sc, WPI_LED_LINK, 5, 5);
        return 0;
    }
    if ((error = wpi_set_timing(sc, ni)) != 0) {
        printf("%s: could not set timing\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Update adapter configuration. */
    sc->rxon.associd = htole16(IEEE80211_AID(ni->ni_associd));
    /* Short preamble and slot time are negotiated when associating. */
    sc->rxon.flags &= ~htole32(WPI_RXON_SHPREAMBLE | WPI_RXON_SHSLOT);
    if (ic->ic_flags & IEEE80211_F_SHSLOT)
        sc->rxon.flags |= htole32(WPI_RXON_SHSLOT);
    if (ic->ic_flags & IEEE80211_F_SHPREAMBLE)
        sc->rxon.flags |= htole32(WPI_RXON_SHPREAMBLE);
    sc->rxon.filter |= htole32(WPI_FILTER_BSS);
    DPRINTF(("rxon chan %d flags %x\n", sc->rxon.chan, sc->rxon.flags));
    error = wpi_cmd(sc, WPI_CMD_RXON, &sc->rxon, sizeof (struct wpi_rxon),
        1);
    if (error != 0) {
        printf("%s: RXON command failed\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Configuration has changed, set TX power accordingly. */
    if ((error = wpi_set_txpower(sc, 1)) != 0) {
        printf("%s: could not set TX power\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Fake a join to init the TX rate. */
    ((struct wpi_node *)ni)->id = WPI_ID_BSS;
    wpi_newassoc(ic, ni, 1);

    /* Add BSS node. */
    memset(&node, 0, sizeof node);
    IEEE80211_ADDR_COPY(node.macaddr, ni->ni_bssid);
    node.id = WPI_ID_BSS;
    node.plcp = (ic->ic_curmode == IEEE80211_MODE_11A) ?
        wpi_rates[WPI_RIDX_OFDM6].plcp : wpi_rates[WPI_RIDX_CCK1].plcp;
    node.action = htole32(WPI_ACTION_SET_RATE);
    node.antenna = WPI_ANTENNA_BOTH;
    DPRINTF(("adding BSS node\n"));
    error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
    if (error != 0) {
        printf("%s: could not add BSS node\n", sc->sc_dev.dv_xname);
        return error;
    }

    /* Start periodic calibration timer. */
    sc->calib_cnt = 0;
    timeout_add_msec(&sc->calib_to, 500);

    /* Link LED always on while associated. */
    wpi_set_led(sc, WPI_LED_LINK, 0, 1);

    /* Enable power-saving mode if requested by user. */
    if (sc->sc_ic.ic_flags & IEEE80211_F_PMGTON)
        (void)wpi_set_pslevel(sc, 0, 3, 1);

    return 0;
}

/*
 * We support CCMP hardware encryption/decryption of unicast frames only.
 * HW support for TKIP really sucks.  We should let TKIP die anyway.
 */
int
wpi_set_key(struct ieee80211com *ic, struct ieee80211_node *ni,
    struct ieee80211_key *k)
{
    struct wpi_softc *sc = (typeof sc)ic->ic_softc;
    struct wpi_node *wn = (typeof wn)ni;
    struct wpi_node_info node;
    uint16_t kflags;

    if ((k->k_flags & IEEE80211_KEY_GROUP) ||
        k->k_cipher != IEEE80211_CIPHER_CCMP)
        return ieee80211_set_key(ic, ni, k);

    kflags = WPI_KFLAG_CCMP | WPI_KFLAG_KID(k->k_id);
    memset(&node, 0, sizeof node);
    node.id = wn->id;
    node.control = WPI_NODE_UPDATE;
    node.flags = WPI_FLAG_SET_KEY;
    node.kflags = htole16(kflags);
    memcpy(node.key, k->k_key, k->k_len);
    DPRINTF(("set key id=%d for node %d\n", k->k_id, node.id));
    return wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
}

void
wpi_delete_key(struct ieee80211com *ic, struct ieee80211_node *ni,
    struct ieee80211_key *k)
{
    struct wpi_softc *sc = (typeof sc)ic->ic_softc;
    struct wpi_node *wn = (typeof wn)ni;
    struct wpi_node_info node;

    if ((k->k_flags & IEEE80211_KEY_GROUP) ||
        k->k_cipher != IEEE80211_CIPHER_CCMP) {
        /* See comment about other ciphers above. */
        ieee80211_delete_key(ic, ni, k);
        return;
    }
    if (ic->ic_state != IEEE80211_S_RUN)
        return;    /* Nothing to do. */
    memset(&node, 0, sizeof node);
    node.id = wn->id;
    node.control = WPI_NODE_UPDATE;
    node.flags = WPI_FLAG_SET_KEY;
    node.kflags = 0;
    DPRINTF(("delete keys for node %d\n", node.id));
    (void)wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
}

int
wpi_post_alive(struct wpi_softc *sc)
{
    int ntries, error;

    /* Check (again) that the radio is not disabled. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    /* NB: Runtime firmware must be up and running. */
    if (!(wpi_prph_read(sc, WPI_APMG_RFKILL) & 1)) {
        printf("%s: radio is disabled by hardware switch\n",
            sc->sc_dev.dv_xname);
        wpi_nic_unlock(sc);
        return EPERM;    /* :-) */
    }
    wpi_nic_unlock(sc);

    /* Wait for thermal sensor to calibrate. */
    for (ntries = 0; ntries < 1000; ntries++) {
        if ((sc->temp = (int)WPI_READ(sc, WPI_UCODE_GP2)) != 0)
            break;
        DELAY(10);
    }
    if (ntries == 1000) {
        printf("%s: timeout waiting for thermal sensor calibration\n",
            sc->sc_dev.dv_xname);
        return ETIMEDOUT;
    }
    DPRINTF(("temperature %d\n", sc->temp));
    return 0;
}

/*
 * The firmware boot code is small and is intended to be copied directly into
 * the NIC internal memory (no DMA transfer.)
 */
int
wpi_load_bootcode(struct wpi_softc *sc, const uint8_t *ucode, int size)
{
    int error, ntries;

    size /= sizeof (uint32_t);

    if ((error = wpi_nic_lock(sc)) != 0)
        return error;

    /* Copy microcode image into NIC memory. */
    wpi_prph_write_region_4(sc, WPI_BSM_SRAM_BASE,
        (const uint32_t *)ucode, size);

    wpi_prph_write(sc, WPI_BSM_WR_MEM_SRC, 0);
    wpi_prph_write(sc, WPI_BSM_WR_MEM_DST, WPI_FW_TEXT_BASE);
    wpi_prph_write(sc, WPI_BSM_WR_DWCOUNT, size);

    /* Start boot load now. */
    wpi_prph_write(sc, WPI_BSM_WR_CTRL, WPI_BSM_WR_CTRL_START);

    /* Wait for transfer to complete. */
    for (ntries = 0; ntries < 1000; ntries++) {
        if (!(wpi_prph_read(sc, WPI_BSM_WR_CTRL) &
            WPI_BSM_WR_CTRL_START))
            break;
        DELAY(10);
    }
    if (ntries == 1000) {
        printf("%s: could not load boot firmware\n",
            sc->sc_dev.dv_xname);
        wpi_nic_unlock(sc);
        return ETIMEDOUT;
    }

    /* Enable boot after power up. */
    wpi_prph_write(sc, WPI_BSM_WR_CTRL, WPI_BSM_WR_CTRL_START_EN);

    wpi_nic_unlock(sc);
    return 0;
}

int
wpi_load_firmware(struct wpi_softc *sc)
{
    struct wpi_fw_info *fw = &sc->fw;
    struct wpi_dma_info *dma = &sc->fw_dma;
    int error;

    /* Copy initialization sections into pre-allocated DMA-safe memory. */
    memcpy(dma->vaddr, fw->init.data, fw->init.datasz);
    bus_dmamap_sync(sc->sc_dmat, dma->map, 0, fw->init.datasz,
        BUS_DMASYNC_PREWRITE);
    memcpy(dma->vaddr + WPI_FW_DATA_MAXSZ,
        fw->init.text, fw->init.textsz);
    bus_dmamap_sync(sc->sc_dmat, dma->map, WPI_FW_DATA_MAXSZ,
        fw->init.textsz, BUS_DMASYNC_PREWRITE);

    /* Tell adapter where to find initialization sections. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    wpi_prph_write(sc, WPI_BSM_DRAM_DATA_ADDR, dma->paddr);
    wpi_prph_write(sc, WPI_BSM_DRAM_DATA_SIZE, fw->init.datasz);
    wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_ADDR,
        dma->paddr + WPI_FW_DATA_MAXSZ);
    wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_SIZE, fw->init.textsz);
    wpi_nic_unlock(sc);

    /* Load firmware boot code. */
    error = wpi_load_bootcode(sc, fw->boot.text, fw->boot.textsz);
    if (error != 0) {
        printf("%s: could not load boot firmware\n",
            sc->sc_dev.dv_xname);
        return error;
    }
    /* Now press "execute". */
    WPI_WRITE(sc, WPI_RESET, 0);

    /* Wait at most one second for first alive notification. */
    if ((error = tsleep_nsec(sc, PCATCH, "wpiinit", SEC_TO_NSEC(1))) != 0) {
        printf("%s: timeout waiting for adapter to initialize\n",
            sc->sc_dev.dv_xname);
        return error;
    }

    /* Copy runtime sections into pre-allocated DMA-safe memory. */
    memcpy(dma->vaddr, fw->main.data, fw->main.datasz);
    bus_dmamap_sync(sc->sc_dmat, dma->map, 0, fw->main.datasz,
        BUS_DMASYNC_PREWRITE);
    memcpy(dma->vaddr + WPI_FW_DATA_MAXSZ,
        fw->main.text, fw->main.textsz);
    bus_dmamap_sync(sc->sc_dmat, dma->map, WPI_FW_DATA_MAXSZ,
        fw->main.textsz, BUS_DMASYNC_PREWRITE);

    /* Tell adapter where to find runtime sections. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    wpi_prph_write(sc, WPI_BSM_DRAM_DATA_ADDR, dma->paddr);
    wpi_prph_write(sc, WPI_BSM_DRAM_DATA_SIZE, fw->main.datasz);
    wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_ADDR,
        dma->paddr + WPI_FW_DATA_MAXSZ);
    wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_SIZE,
        WPI_FW_UPDATED | fw->main.textsz);
    wpi_nic_unlock(sc);

    return 0;
}

int
wpi_read_firmware(struct wpi_softc *sc)
{
    struct wpi_fw_info *fw = &sc->fw;
    const struct wpi_firmware_hdr *hdr;
    int error;

    /* Read firmware image from filesystem. */
    if ((error = loadfirmware("wpi-3945abg", &fw->data, &fw->datalen)) != 0) {
        printf("%s: error, %d, could not read firmware %s\n",
            sc->sc_dev.dv_xname, error, "wpi-3945abg");
        return error;
    }
    if (fw->datalen < sizeof (*hdr)) {
        printf("%s: truncated firmware header: %zu bytes\n",
            sc->sc_dev.dv_xname, fw->datalen);
        free(fw->data, M_DEVBUF, fw->datalen);
        return EINVAL;
    }
    /* Extract firmware header information. */
    hdr = (struct wpi_firmware_hdr *)fw->data;
    fw->main.textsz = letoh32(hdr->main_textsz);
    fw->main.datasz = letoh32(hdr->main_datasz);
    fw->init.textsz = letoh32(hdr->init_textsz);
    fw->init.datasz = letoh32(hdr->init_datasz);
    fw->boot.textsz = letoh32(hdr->boot_textsz);
    fw->boot.datasz = 0;

    /* Sanity-check firmware header. */
    if (fw->main.textsz > WPI_FW_TEXT_MAXSZ ||
        fw->main.datasz > WPI_FW_DATA_MAXSZ ||
        fw->init.textsz > WPI_FW_TEXT_MAXSZ ||
        fw->init.datasz > WPI_FW_DATA_MAXSZ ||
        fw->boot.textsz > WPI_FW_BOOT_TEXT_MAXSZ ||
        (fw->boot.textsz & 3) != 0) {
        printf("%s: invalid firmware header\n", sc->sc_dev.dv_xname);
        free(fw->data, M_DEVBUF, fw->datalen);
        return EINVAL;
    }

    /* Check that all firmware sections fit. */
    if (fw->datalen < sizeof (*hdr) + fw->main.textsz + fw->main.datasz +
        fw->init.textsz + fw->init.datasz + fw->boot.textsz) {
        printf("%s: firmware file too short: %zu bytes\n",
            sc->sc_dev.dv_xname, fw->datalen);
        free(fw->data, M_DEVBUF, fw->datalen);
        return EINVAL;
    }

    /* Get pointers to firmware sections. */
    fw->main.text = (const uint8_t *)(hdr + 1);
    fw->main.data = fw->main.text + fw->main.textsz;
    fw->init.text = fw->main.data + fw->main.datasz;
    fw->init.data = fw->init.text + fw->init.textsz;
    fw->boot.text = fw->init.data + fw->init.datasz;

    return 0;
}

int
wpi_clock_wait(struct wpi_softc *sc)
{
    int ntries;

    /* Set "initialization complete" bit. */
    WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_INIT_DONE);

    /* Wait for clock stabilization. */
    for (ntries = 0; ntries < 25000; ntries++) {
        if (WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_MAC_CLOCK_READY)
            return 0;
        DELAY(100);
    }
    printf("%s: timeout waiting for clock stabilization\n",
        sc->sc_dev.dv_xname);
    return ETIMEDOUT;
}

int
wpi_apm_init(struct wpi_softc *sc)
{
    int error;

    WPI_SETBITS(sc, WPI_ANA_PLL, WPI_ANA_PLL_INIT);
    /* Disable L0s. */
    WPI_SETBITS(sc, WPI_GIO_CHICKEN, WPI_GIO_CHICKEN_L1A_NO_L0S_RX);

    if ((error = wpi_clock_wait(sc)) != 0)
        return error;

    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    /* Enable DMA. */
    wpi_prph_write(sc, WPI_APMG_CLK_ENA,
        WPI_APMG_CLK_DMA_CLK_RQT | WPI_APMG_CLK_BSM_CLK_RQT);
    DELAY(20);
    /* Disable L1. */
    wpi_prph_setbits(sc, WPI_APMG_PCI_STT, WPI_APMG_PCI_STT_L1A_DIS);
    wpi_nic_unlock(sc);

    return 0;
}

void
wpi_apm_stop_master(struct wpi_softc *sc)
{
    int ntries;

    WPI_SETBITS(sc, WPI_RESET, WPI_RESET_STOP_MASTER);

    if ((WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_PS_MASK) ==
        WPI_GP_CNTRL_MAC_PS)
        return;    /* Already asleep. */

    for (ntries = 0; ntries < 100; ntries++) {
        if (WPI_READ(sc, WPI_RESET) & WPI_RESET_MASTER_DISABLED)
            return;
        DELAY(10);
    }
    printf("%s: timeout waiting for master\n", sc->sc_dev.dv_xname);
}

void
wpi_apm_stop(struct wpi_softc *sc)
{
    wpi_apm_stop_master(sc);
    WPI_SETBITS(sc, WPI_RESET, WPI_RESET_SW);
}

void
wpi_nic_config(struct wpi_softc *sc)
{
    pcireg_t reg;
    uint8_t rev;

    /* Voodoo from the reference driver. */
    reg = pci_conf_read(sc->sc_pct, sc->sc_pcitag, PCI_CLASS_REG);
    rev = PCI_REVISION(reg);
    if ((rev & 0xc0) == 0x40)
        WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_ALM_MB);
    else if (!(rev & 0x80))
        WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_ALM_MM);

    if (sc->cap == 0x80)
        WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_SKU_MRC);

    if ((letoh16(sc->rev) & 0xf0) == 0xd0)
        WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_REV_D);
    else
        WPI_CLRBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_REV_D);

    if (sc->type > 1)
        WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_TYPE_B);
}

int
wpi_hw_init(struct wpi_softc *sc)
{
    int chnl, ntries, error;

    /* Clear pending interrupts. */
    WPI_WRITE(sc, WPI_INT, 0xffffffff);

    if ((error = wpi_apm_init(sc)) != 0) {
        printf("%s: could not power ON adapter\n",
            sc->sc_dev.dv_xname);
        return error;
    }

    /* Select VMAIN power source. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    wpi_prph_clrbits(sc, WPI_APMG_PS, WPI_APMG_PS_PWR_SRC_MASK);
    wpi_nic_unlock(sc);
    /* Spin until VMAIN gets selected. */
    for (ntries = 0; ntries < 5000; ntries++) {
        if (WPI_READ(sc, WPI_GPIO_IN) & WPI_GPIO_IN_VMAIN)
            break;
        DELAY(10);
    }
    if (ntries == 5000) {
        printf("%s: timeout selecting power source\n",
            sc->sc_dev.dv_xname);
        return ETIMEDOUT;
    }

    /* Perform adapter initialization. */
    (void)wpi_nic_config(sc);

    /* Initialize RX ring. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    /* Set physical address of RX ring. */
    WPI_WRITE(sc, WPI_FH_RX_BASE, sc->rxq.desc_dma.paddr);
    /* Set physical address of RX read pointer. */
    WPI_WRITE(sc, WPI_FH_RX_RPTR_ADDR, sc->shared_dma.paddr +
        offsetof(struct wpi_shared, next));
    WPI_WRITE(sc, WPI_FH_RX_WPTR, 0);
    /* Enable RX. */
    WPI_WRITE(sc, WPI_FH_RX_CONFIG,
        WPI_FH_RX_CONFIG_DMA_ENA |
        WPI_FH_RX_CONFIG_RDRBD_ENA |
        WPI_FH_RX_CONFIG_WRSTATUS_ENA |
        WPI_FH_RX_CONFIG_MAXFRAG |
        WPI_FH_RX_CONFIG_NRBD(WPI_RX_RING_COUNT_LOG) |
        WPI_FH_RX_CONFIG_IRQ_DST_HOST |
        WPI_FH_RX_CONFIG_IRQ_RBTH(1));
    (void)WPI_READ(sc, WPI_FH_RSSR_TBL);    /* barrier */
    WPI_WRITE(sc, WPI_FH_RX_WPTR, (WPI_RX_RING_COUNT - 1) & ~7);
    wpi_nic_unlock(sc);

    /* Initialize TX rings. */
    if ((error = wpi_nic_lock(sc)) != 0)
        return error;
    wpi_prph_write(sc, WPI_ALM_SCHED_MODE, 2);    /* bypass mode */
    wpi_prph_write(sc, WPI_ALM_SCHED_ARASTAT, 1);    /* enable RA0 */
    /* Enable all 6 TX rings. */
    wpi_prph_write(sc, WPI_ALM_SCHED_TXFACT, 0x3f);
    wpi_prph_write(sc, WPI_ALM_SCHED_SBYPASS_MODE1, 0x10000);
    wpi_prph_write(sc, WPI_ALM_SCHED_SBYPASS_MODE2, 0x30002);
    wpi_prph_write(sc, WPI_ALM_SCHED_TXF4MF, 4);
    wpi_prph_write(sc, WPI_ALM_SCHED_TXF5MF, 5);
    /* Set physical address of TX rings. */
    WPI_WRITE(sc, WPI_FH_TX_BASE, sc->shared_dma.paddr);
    WPI_WRITE(sc, WPI_FH_MSG_CONFIG, 0xffff05a5);

    /* Enable all DMA channels. */
    for (chnl = 0; chnl < WPI_NDMACHNLS; chnl++) {
        WPI_WRITE(sc, WPI_FH_CBBC_CTRL(chnl), 0);
        WPI_WRITE(sc, WPI_FH_CBBC_BASE(chnl), 0);
        WPI_WRITE(sc, WPI_FH_TX_CONFIG(chnl), 0x80200008);
    }
    wpi_nic_unlock(sc);
    (void)WPI_READ(sc, WPI_FH_TX_BASE);    /* barrier */

    /* Clear "radio off" and "commands blocked" bits. */
    WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);
    WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_CMD_BLOCKED);

    /* Clear pending interrupts. */
    WPI_WRITE(sc, WPI_INT, 0xffffffff);
    /* Enable interrupts. */
    WPI_WRITE(sc, WPI_MASK, WPI_INT_MASK);

    /* _Really_ make sure "radio off" bit is cleared! */
    WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);
    WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);

    if ((error = wpi_load_firmware(sc)) != 0) {
        printf("%s: could not load firmware\n", sc->sc_dev.dv_xname);
        return error;
    }
    /* Wait at most one second for firmware alive notification. */
    if ((error = tsleep_nsec(sc, PCATCH, "wpiinit", SEC_TO_NSEC(1))) != 0) {
        printf("%s: timeout waiting for adapter to initialize\n",
            sc->sc_dev.dv_xname);
        return error;
    }
    /* Do post-firmware initialization. */
    return wpi_post_alive(sc);
}

void
wpi_hw_stop(struct wpi_softc *sc)
{
    int chnl, qid, ntries;
    uint32_t tmp;

    WPI_WRITE(sc, WPI_RESET, WPI_RESET_NEVO);

    /* Disable interrupts. */
    WPI_WRITE(sc, WPI_MASK, 0);
    WPI_WRITE(sc, WPI_INT, 0xffffffff);
    WPI_WRITE(sc, WPI_FH_INT, 0xffffffff);

    /* Make sure we no longer hold the NIC lock. */
    wpi_nic_unlock(sc);

    if (wpi_nic_lock(sc) == 0) {
        /* Stop TX scheduler. */
        wpi_prph_write(sc, WPI_ALM_SCHED_MODE, 0);
        wpi_prph_write(sc, WPI_ALM_SCHED_TXFACT, 0);

        /* Stop all DMA channels. */
        for (chnl = 0; chnl < WPI_NDMACHNLS; chnl++) {
            WPI_WRITE(sc, WPI_FH_TX_CONFIG(chnl), 0);
            for (ntries = 0; ntries < 100; ntries++) {
                tmp = WPI_READ(sc, WPI_FH_TX_STATUS);
                if ((tmp & WPI_FH_TX_STATUS_IDLE(chnl)) ==
                    WPI_FH_TX_STATUS_IDLE(chnl))
                    break;
                DELAY(10);
            }
        }
        wpi_nic_unlock(sc);
    }

    /* Stop RX ring. */
    wpi_reset_rx_ring(sc, &sc->rxq);

    /* Reset all TX rings. */
    for (qid = 0; qid < WPI_NTXQUEUES; qid++)
        wpi_reset_tx_ring(sc, &sc->txq[qid]);

    if (wpi_nic_lock(sc) == 0) {
        wpi_prph_write(sc, WPI_APMG_CLK_DIS, WPI_APMG_CLK_DMA_CLK_RQT);
        wpi_nic_unlock(sc);
    }
    DELAY(5);
    /* Power OFF adapter. */
    wpi_apm_stop(sc);
}

int
wpi_init(struct ifnet *ifp)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    struct ieee80211com *ic = &sc->sc_ic;
    int error;

#ifdef notyet
    /* Check that the radio is not disabled by hardware switch. */
    if (!(WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_RFKILL)) {
        printf("%s: radio is disabled by hardware switch\n",
            sc->sc_dev.dv_xname);
        error = EPERM;    /* :-) */
        goto fail;
    }
#endif
    /* Read firmware images from the filesystem. */
    if ((error = wpi_read_firmware(sc)) != 0) {
        printf("%s: could not read firmware\n", sc->sc_dev.dv_xname);
        goto fail;
    }

    /* Initialize hardware and upload firmware. */
    error = wpi_hw_init(sc);
    free(sc->fw.data, M_DEVBUF, sc->fw.datalen);
    if (error != 0) {
        printf("%s: could not initialize hardware\n",
            sc->sc_dev.dv_xname);
        goto fail;
    }

    /* Configure adapter now that it is ready. */
    if ((error = wpi_config(sc)) != 0) {
        printf("%s: could not configure device\n",
            sc->sc_dev.dv_xname);
        goto fail;
    }

    ifq_clr_oactive(&ifp->if_snd);
    ifp->if_flags |= IFF_RUNNING;

    if (ic->ic_opmode != IEEE80211_M_MONITOR)
        ieee80211_begin_scan(ifp);
    else
        ieee80211_new_state(ic, IEEE80211_S_RUN, -1);

    return 0;

fail:    wpi_stop(ifp, 1);
    return error;
}

void
wpi_stop(struct ifnet *ifp, int disable)
{
    struct wpi_softc *sc = (typeof sc)ifp->if_softc;
    struct ieee80211com *ic = &sc->sc_ic;

    ifp->if_timer = sc->sc_tx_timer = 0;
    ifp->if_flags &= ~IFF_RUNNING;
    ifq_clr_oactive(&ifp->if_snd);

    ieee80211_new_state(ic, IEEE80211_S_INIT, -1);

    /* Power OFF hardware. */
    wpi_hw_stop(sc);
}
